[1] (1R,2S)-(−)-Ephedrine by Asch

Query Query

Date

75 reactions in Reaxys

2016-09-09 04h:46m:51s (EST)

75 reactions in Reaxys

2016-09-09 04h:47m:13s (EST)

1. Query

Results

H N H

Search as: As drawn, No mixtures, No charges, No radicals 2. Query

(1. Query) AND itemno in (1)

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H N

O O

Rx-ID: 41227745 View in Reaxys 1/75 Yield

Conditions & References (1R,2S)-2-(methylamino)-1-phenylpropan-1-ol hydrochloride (1): To a solution of benzyl carbamate 16 (0.10 g) in methanol was added 10percent Pd/C (10 mg). The resulting solution was stirred under hydrogen (1 atmosphere) for 12 h at room temperature until completion of the reaction as monitored by thin-layer chromatography (TLC). The reaction mixture was filtered through a celite pad to remove the catalyst, and the filtrate was concentrated in vacuo to get (1R, 2S)-ephedrine as colourless oil to which methanolic HCl (3N, 3mL) was added and stirred for 30 min. The reaction mixture was concentrated to give (1R, 2S)-ephedrine hydrochloride 1 as a colorless solid (52 mg). With palladium 10 on activated carbon, hydrogen in methanol, Time= 12h, T= 20 °C , p= 760.051Torr , enantioselective reaction Lalwani, Komal G.; Sudalai, Arumugam; Tetrahedron Letters; vol. 56; nb. 46; (2015); p. 6488 - 6490 View in Reaxys OH

H N

H racemate

Rx-ID: 3498941 View in Reaxys 2/75 Yield

Conditions & References

80 %

With lithium aluminium tetrahydride in tetrahydrofuran, T= 60 °C Fujita, Makoto; Hiyama, Tamejiro; Journal of the American Chemical Society; vol. 106; nb. 16; (1984); p. 4629 4630 View in Reaxys

H N

Rx-ID: 28455482 View in Reaxys 3/75 Yield

Conditions & References

67 %

With palladium dihydroxide, hydrogen in ethanol, T= 20 °C , p= 2585.81Torr , Inert atmosphere Kim, Yongeun; Ha, Hyun-Joon; Yun, Sae Young; Lee, Won Koo; Chemical Communications; nb. 36; (2008); p. 4363 - 4365 View in Reaxys

NH OH 2

H N

HO O

OH O

Rx-ID: 31615932 View in Reaxys 4/75

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Yield

Conditions & References

64 %

3 :Example 3 : (li~,2i~)-4-oxo-l,2-cyclopentanedicarboxylic acid and recovery of ephedrine.; To a solution of (li~, 2i~)-4-oxo-l,2-cyclopentanedicarboxylic acid salt with (lR,2S)-(-)- ephedrine (1 :2) (251 g, 0.5 mol) was added 8 N aqueous KOH (199.21 g, 1.10 mole) and the mixture was stirred for 5 minutes. 2-Methyltetrahydrofuran (688 ml) was added and the mixture was stirred vigorously for 20 minutes. The two layers were separated and the aqueous phase was acidified with HC1. The 2-methyltetrahydrofuran organic phase contained the ephedrine, which could be recycled from that phase. The aqueous phase was then evaporated to dryness on the rotavapor and the residue recrystallized from water (50 ml) to yield 55.15 g (64 percent yield) of (li~,2i~)-4-oxo-l,2-cyclopentanedicarboxylic acid as an off white solid. The 2-methyltetrahydrofuran solution of ephedrine was evaporated to dryness on the rotavapor to yield crude ephedrine as a yellow oil, which solidified on standing after 3 days. The crude ephedrine was dissolved in 2-methyltetrahydrofuran (400 ml) and the mixture made acidic with HC1 in isopropanol. The solid material was filtered and washed with 2-methyltetrahydrofuran (50 ml). The solid ephedrine hydrochloride was dried under vacuum at 50°C before being dissolved in water (300 ml) at 40°C.Sufficient potassium carbonate was added portionwise to the warm aqueous solution, until a two-phase system was obtained. 2-Methyltetrahydrofuran (200 ml) was added and the mixture stirred vigorously for 5 minutes. The two layers were separated and the aqueous phase extracted with 2-methyltetrahydrofuran (200 ml). The combined organic layers were dried over Na2S04, filtered and evaporated to dryness to yield 124.7 g (75percent yield) of recovered ephedrine as a white solid. Stage 1: With potassium hydroxide in water, Time= 0.0833333h Stage 2: With hydrogenchloride in water Patent; ORTHO-MCNEIL-JANSSEN PHARMACEUTICALS, INC; ORMEROD, Dominic John; DEPRE, Dominique Paul Michel; HORVATH, Andras; WO2011/113859; (2011); (A1) English View in Reaxys

H 2N HO

H N

Rx-ID: 772212 View in Reaxys 5/75 Yield 64 %

Conditions & References With platinum(IV) oxide, hydrogen in methanol, acetic acid n-butyl ester, Time= 1h, p= 2250.2Torr Cervinka, Otakar; Struzka, Vladimir; Collection of Czechoslovak Chemical Communications; vol. 55; nb. 11; (1990); p. 2685 - 2691 View in Reaxys With ethanol, palladium, Hydrogenation Freudenberg; Schoeffel; Braun; Journal of the American Chemical Society; vol. 54; (1932); p. 234 View in Reaxys With diethyl ether, water, platinum, Hydrogenation Patent; Knoll A.G.; DE548459; (1930); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 18; p. 3032 View in Reaxys With diethyl ether, aluminium amalgam, water Patent; Knoll A.G.; DE548459; (1930); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 18; p. 3032 View in Reaxys With zinc(II) tetrahydroborate, 1.) ether, 0 deg C, 2.) -76 deg C, 1 h, Multistep reaction Jackson, W. Roy; Jacobs, Howard A.; Jayatilake, Gamini S.; Matthews, Barry R.; Watson, Keith G.; Australian Journal of Chemistry; vol. 43; nb. 12; (1990); p. 2045 - 2062 View in Reaxys

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H N

Rx-ID: 3043731 View in Reaxys 6/75 Yield

Conditions & References

80 %

With lithium aluminium tetrahydride in tetrahydrofuran, Time= 1.5h, T= 60 °C Fujita, Makoto; Hiyama, Tamejiro; Journal of Organic Chemistry; vol. 53; nb. 23; (1988); p. 5415 - 5421 View in Reaxys

OH O

H N

Rx-ID: 3648539 View in Reaxys 7/75 Yield

Conditions & References

100 %

With diethylamine, palladium diacetate, triphenylphosphine-3,3',3''-trisulfonic acid trisodium salt in water, acetonitrile, Time= 0.25h, Ambient temperature Genet, Jean Pierre; Blart, Errol; Savignac, Monique; Lemeune, Stephane; Lemaire-Audoire, Sandrine; Paris, Jean-Marc; Bernard, Jean-Marie; Tetrahedron; vol. 50; nb. 2; (1991); p. 497 - 503 View in Reaxys

OH N H

H N

N H

H 2N

Rx-ID: 3198554 View in Reaxys 8/75 Yield

Conditions & References With hydrogenchloride, hydrogen, palladium on activated charcoal in ethanol, Time= 12h, T= 45 °C , p= 4045.3Torr , Yield given. Yields of byproduct given Takahashi; Tomita; Noguchi; Chemical and Pharmaceutical Bulletin; vol. 29; nb. 11; (1981); p. 3387 - 3391 View in Reaxys

OH N H

H N

H 2N

Rx-ID: 3198555 View in Reaxys 9/75 Yield

Conditions & References With hydrogenchloride, hydrogen, palladium on activated charcoal in ethanol, Time= 8h, T= 50 - 60 °C , p= 4413.05Torr , Yield given. Yields of byproduct given Takahashi; Tomita; Noguchi; Chemical and Pharmaceutical Bulletin; vol. 29; nb. 11; (1981); p. 3387 - 3391 View in Reaxys

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H N

NH 2

Rx-ID: 3202900 View in Reaxys 10/75 Yield

Conditions & References With hydrogenchloride, hydrogen, palladium on activated charcoal in ethanol, Time= 12h, T= 45 °C , p= 4045.3Torr Takahashi; Inagaki; Chemical and Pharmaceutical Bulletin; vol. 30; nb. 3; (1982); p. 922 - 926 View in Reaxys

H N

H HN

OH H

Rx-ID: 3043728 View in Reaxys 11/75 Yield

Conditions & References With lithium aluminium tetrahydride in tetrahydrofuran, Time= 2h, T= 60 °C , Yield given. Yields of byproduct given Buckley, Thomas F.; Rapoport, Henry; Journal of the American Chemical Society; vol. 103; nb. 20; (1981); p. 6157 - 6163 View in Reaxys

H N

Rx-ID: 19230807 View in Reaxys 12/75 Yield

Conditions & References Reaction Steps: 2 1: PhMe2SiH / trifluoroacetic acid / 2.5 h / 0 °C 2: 80 percent / lithium aluminium hydride / tetrahydrofuran / 60 °C With lithium aluminium tetrahydride, dimethylphenylsilane in tetrahydrofuran, trifluoroacetic acid Fujita, Makoto; Hiyama, Tamejiro; Journal of the American Chemical Society; vol. 106; nb. 16; (1984); p. 4629 4630 View in Reaxys

H H 2N

OH H N

N H

(1S,2R)-1-methylamino-1-phenyl-propan-2-ol (C10H15NO)

Rx-ID: 19970176 View in Reaxys 13/75 Yield

Conditions & References Reaction Steps: 3 1: 77 percent / benzene / 3 h / Heating 2: 70 percent / diethyl ether / 18 h / Ambient temperature 3: conc HCl, H2 / 10percent Pd-carbon / ethanol / 12 h / 45 °C / 4045.3 Torr With hydrogenchloride, hydrogen, palladium on activated charcoal in diethyl ether, ethanol, benzene

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Takahashi; Inagaki; Chemical and Pharmaceutical Bulletin; vol. 30; nb. 3; (1982); p. 922 - 926 View in Reaxys Reaction Steps: 3 1: benzene 2: 79 percent / tetrahydrofuran / 40 deg C, 6 h, RT, 37 h 3: conc. HCl, hydrogen / 10percent Pd-carbon / ethanol / 8 h / 50 - 60 °C / 4413.05 Torr With hydrogenchloride, hydrogen, palladium on activated charcoal in tetrahydrofuran, ethanol, benzene Takahashi; Tomita; Noguchi; Chemical and Pharmaceutical Bulletin; vol. 29; nb. 11; (1981); p. 3387 - 3391 View in Reaxys Reaction Steps: 3 1: 79 percent / benzene / 36 h / Ambient temperature 2: 70 percent / lithium aluminium hydride / diethyl ether / 3.25 h / Heating 3: conc. HCl, hydrogen / 10percent Pd-carbon / ethanol / 12 h / 45 °C / 4045.3 Torr With hydrogenchloride, lithium aluminium tetrahydride, hydrogen, palladium on activated charcoal in diethyl ether, ethanol, benzene Takahashi; Tomita; Noguchi; Chemical and Pharmaceutical Bulletin; vol. 29; nb. 11; (1981); p. 3387 - 3391 View in Reaxys

H N

Rx-ID: 4677217 View in Reaxys 14/75 Yield

Conditions & References With lithium aluminium tetrahydride in diethyl ether, Time= 2h, T= -10 - 20 °C , Yield given Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467 View in Reaxys

OH H

H N

Rx-ID: 17291089 View in Reaxys 15/75 Yield

Conditions & References Reaction Steps: 2 1: pyridine / diethyl ether 2: 3.) NaBH4 With pyridine, sodium tetrahydroborate in diethyl ether Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467 View in Reaxys Reaction Steps: 4 1: pyridine / diethyl ether 2: 2.) NaBH4, 3.) H2O, H+ / 1.) Et2O 3: diethyl ether / 1 h / -30 °C 4: LiAlH4 / diethyl ether / 2 h / -10 - 20 °C With pyridine, sodium tetrahydroborate, lithium aluminium tetrahydride, water, hydrogen cation in diethyl ether Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467 View in Reaxys Reaction Steps: 3 1: 100 percent / imidazole, DMAP / diethyl ether 2: 2.) 2 M HCl / 1.) ether, reflux, 2 h 3: 2.) NaBH4 / 1.) ether, 0 deg C, 30 min, 2.) from 10 deg C to RT

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With 1H-imidazole, hydrogenchloride, 4-(N,N-dimethlyamino)pyridine, sodium tetrahydroborate in diethyl ether Jackson, W. Roy; Jacobs, Howard A.; Jayatilake, Gamini S.; Matthews, Barry R.; Watson, Keith G.; Australian Journal of Chemistry; vol. 43; nb. 12; (1990); p. 2045 - 2062 View in Reaxys Reaction Steps: 3 1: 100 percent / imidazole, DMAP / diethyl ether 2: 2.) 2 M HCl / 1.) ether, reflux, 2 h 3: 2.) Zn(BH4)2 / 1.) ether, 0 deg C, 2.) -76 deg C, 1 h With 1H-imidazole, hydrogenchloride, 4-(N,N-dimethlyamino)pyridine, zinc(II) tetrahydroborate in diethyl ether Jackson, W. Roy; Jacobs, Howard A.; Jayatilake, Gamini S.; Matthews, Barry R.; Watson, Keith G.; Australian Journal of Chemistry; vol. 43; nb. 12; (1990); p. 2045 - 2062 View in Reaxys

OH E

H N

(1S,2R)-1-methylamino-1-phenyl-propan-2-ol (C10H15NO)

Rx-ID: 19982855 View in Reaxys 16/75 Yield

Conditions & References Reaction Steps: 2 1: 70 percent / diethyl ether / 18 h / Ambient temperature 2: conc HCl, H2 / 10percent Pd-carbon / ethanol / 12 h / 45 °C / 4045.3 Torr With hydrogenchloride, hydrogen, palladium on activated charcoal in diethyl ether, ethanol Takahashi; Inagaki; Chemical and Pharmaceutical Bulletin; vol. 30; nb. 3; (1982); p. 922 - 926 View in Reaxys

OH E

H N

(1S,2R)-1-methylamino-1-phenyl-propan-2-ol (C10H15NO)

Rx-ID: 20079638 View in Reaxys 17/75 Yield

Conditions & References Reaction Steps: 2 1: 79 percent / tetrahydrofuran / 40 deg C, 6 h, RT, 37 h 2: conc. HCl, hydrogen / 10percent Pd-carbon / ethanol / 8 h / 50 - 60 °C / 4413.05 Torr With hydrogenchloride, hydrogen, palladium on activated charcoal in tetrahydrofuran, ethanol Takahashi; Tomita; Noguchi; Chemical and Pharmaceutical Bulletin; vol. 29; nb. 11; (1981); p. 3387 - 3391 View in Reaxys

OH N

H N

(1S,2R)-1-methylamino-1-phenyl-propan-2-ol (C10H15NO)

Rx-ID: 20080032 View in Reaxys 18/75 Yield

Conditions & References Reaction Steps: 2 1: 70 percent / lithium aluminium hydride / diethyl ether / 3.25 h / Heating 2: conc. HCl, hydrogen / 10percent Pd-carbon / ethanol / 12 h / 45 °C / 4045.3 Torr With hydrogenchloride, lithium aluminium tetrahydride, hydrogen, palladium on activated charcoal in diethyl ether, ethanol Takahashi; Tomita; Noguchi; Chemical and Pharmaceutical Bulletin; vol. 29; nb. 11; (1981); p. 3387 - 3391

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View in Reaxys

N O

O N

H O

H N

Rx-ID: 3934304 View in Reaxys 19/75 Yield

Conditions & References

60 %, 66 %

With di-isopropyl azodicarboxylate, triphenylphosphine in diethyl ether, Ambient temperature Poelert, Martin A.; Hulshof, L. A.; Kellogg, Richard M.; Recueil des Travaux Chimiques des Pays-Bas; vol. 113; nb. 7/8; (1994); p. 355 - 364 View in Reaxys

H N

d-pseudoephedrine hydrochloride

Rx-ID: 7364049 View in Reaxys 20/75 Yield

Conditions & References With barium dihydroxide, water, T= 170 - 180 °C , im Einschlussrohr Spaeth; Goehring; Monatshefte fuer Chemie; vol. 41; (1920); p. 325 View in Reaxys Schmidt; Calliess; Archiv der Pharmazie (Weinheim, Germany); vol. 250; (1912); p. 156; Chem. Zentralbl.; vol. 82; nb. II; (1911); p. 33 View in Reaxys With hydrogenchloride Schmidt,E.; Archiv der Pharmazie (Weinheim, Germany); vol. 246; (1908); p. 217 View in Reaxys

H N Si O

Rx-ID: 17294587 View in Reaxys 21/75 Yield

Conditions & References Reaction Steps: 3 1: 2.) NaBH4, 3.) H2O, H+ / 1.) Et2O 2: diethyl ether / 1 h / -30 °C 3: LiAlH4 / diethyl ether / 2 h / -10 - 20 °C With sodium tetrahydroborate, lithium aluminium tetrahydride, water, hydrogen cation in diethyl ether Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467 View in Reaxys Reaction Steps: 2 1: 2.) 2 M HCl / 1.) ether, reflux, 2 h 2: 2.) NaBH4 / 1.) ether, 0 deg C, 30 min, 2.) from 10 deg C to RT With hydrogenchloride, sodium tetrahydroborate Jackson, W. Roy; Jacobs, Howard A.; Jayatilake, Gamini S.; Matthews, Barry R.; Watson, Keith G.; Australian Journal of Chemistry; vol. 43; nb. 12; (1990); p. 2045 - 2062 View in Reaxys

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Reaction Steps: 2 1: 2.) 2 M HCl / 1.) ether, reflux, 2 h 2: 2.) Zn(BH4)2 / 1.) ether, 0 deg C, 2.) -76 deg C, 1 h With hydrogenchloride, zinc(II) tetrahydroborate Jackson, W. Roy; Jacobs, Howard A.; Jayatilake, Gamini S.; Matthews, Barry R.; Watson, Keith G.; Australian Journal of Chemistry; vol. 43; nb. 12; (1990); p. 2045 - 2062 View in Reaxys

H N

racemate

Rx-ID: 438164 View in Reaxys 22/75 Yield

Conditions & References With L-(+)-tartaric acid Patent; I.G. Farbenind.; DE549970; (1929); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 19; p. 1446,1447 View in Reaxys Patent; I.G. Farbenind.; DE551778; (1929) View in Reaxys With lactase, Petroleum ether, benzene Lecoq; Bulletin de la Societe Royale des Sciences de Liege; vol. 12; (1943); p. 316 View in Reaxys With (2S,3S)-2,3-dihydroxybutanedioic acid Patent; I.G. Farbenind.; DE553788; (1927); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 18; p. 3032 View in Reaxys With hydrogenchloride, (S)-(+)-2-methyl-2-phenylbutanedioic acid, 1.) CHCl3, reflux, 30 min, 2.) Et2O, room temp., 30 min, Yield given. Multistep reaction Gharpure, Milind M.; Rao, A. S.; Synthesis; nb. 5; (1988); p. 410 - 411 View in Reaxys

H N

H 2N H

Rx-ID: 17289430 View in Reaxys 23/75 Yield

Conditions & References Reaction Steps: 2 1: diethyl ether / 1 h / -30 °C 2: LiAlH4 / diethyl ether / 2 h / -10 - 20 °C With lithium aluminium tetrahydride in diethyl ether Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467 View in Reaxys

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H N

Rx-ID: 17293024 View in Reaxys 24/75 Yield

Conditions & References Reaction Steps: 2 1: 3.) NaBH4 2: LiAlH4 / diethyl ether / 1 h / Heating With sodium tetrahydroborate, lithium aluminium tetrahydride in diethyl ether Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467 View in Reaxys

H N O

Rx-ID: 17308073 View in Reaxys 25/75 Yield

H H 2N

H 2N

O– H

NH 2 N

H N

H O

Rx-ID: 29581123 View in Reaxys 26/75 Yield

Conditions & References With 1,3-bis[tris(hydroxymethyl)methylamino]-propane, Ephedra sinica Stapf (1R,2S)-norephedrine N-methyltransferase, glycerol, threo-1,4-dimercapto-2,3-butanediol, T= 37 °C , pH= 8.5, aq. buffer, Enzymatic reaction Krizevski, Raz; Bar, Einat; Shalit, Or; Sitrit, Yaron; Ben-Shabat, Shimon; Lewinsohn, Efraim; Phytochemistry; vol. 71; nb. 8-9; (2010); p. 895 - 903 View in Reaxys

H N

OH H N H

Rx-ID: 4698041 View in Reaxys 27/75 Yield

Conditions & References With lithium aluminium tetrahydride in diethyl ether, Time= 1h, Heating, Yield given Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467

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View in Reaxys

H N

Rx-ID: 4698768 View in Reaxys 28/75 Yield

H N

Rx-ID: 356232 View in Reaxys 29/75 Yield

Conditions & References With sulfuric acid, acetic anhydride, anschliessend Erhitzen des Reaktionsprodukts mit wss. Schwefelsaeure Patent; Legerlotz; DE585164; (1932); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 20; p. 962 View in Reaxys With hydrogenchloride Spaeth; Goehring; Monatshefte fuer Chemie; vol. 41; (1920); p. 325 View in Reaxys With hydrogenchloride, Gleichgewicht dieser Reaktion Emde; Helvetica Chimica Acta; vol. 12; (1929); p. 393 View in Reaxys

H N

OH H

H HO

H N

Rx-ID: 3210533 View in Reaxys 30/75 Yield

Conditions & References in dimethyl sulfoxide, T= 25 °C , Equilibrium constant Zingg, S. P.; Arnett, Edward M.; McPhail, Andrew T.; Bothner-By, Aksel A.; Gilkerson, W. R.; Journal of the American Chemical Society; vol. 110; nb. 5; (1988); p. 1565 - 1580 View in Reaxys

O H

OH OH

H H

N H OH

H N

OH OH

Rx-ID: 3210537 View in Reaxys 31/75

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Yield

(1R:2S)-2-<methyl-benzyl-amino>-1-phenyl-propanol-(1)-hydrochloride

H N

Rx-ID: 7364048 View in Reaxys 32/75 Yield

Conditions & References With ethanol, palladium, Hydrogenation Patent; I.G. Farbenind.; DE538455; (1930); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 18; p. 3046 View in Reaxys With ethanol, water, Hydrogenation Patent; I.G. Farbenind.; DE538455; (1930); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 18; p. 3046 View in Reaxys

N-methyl-<l-ephedrine>-iodo methylate

H N

Rx-ID: 7364051 View in Reaxys 33/75 Yield

Conditions & References With sodium amalgam, water Schmidt; Eberhard; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 64,66 View in Reaxys

H N

Rx-ID: 21451827 View in Reaxys 34/75 Yield

Conditions & References Reaction Steps: 2 2: H2O With water Abdallah, Hassan; Gree, Rene; Carrie, Robert; Tetrahedron Letters; vol. 23; nb. 5; (1982); p. 503 - 506 View in Reaxys

H N

H N H

Rx-ID: 437423 View in Reaxys 35/75 Yield

Conditions & References With lithium aluminium tetrahydride

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Takamatsu; Yakugaku Zasshi; vol. 76; (1956); p. 1227; ; (1957); p. 4304 View in Reaxys With sodium tetrahydroborate Takamatsu; Yakugaku Zasshi; vol. 76; (1956); p. 1227; ; (1957); p. 4304 View in Reaxys

H N

H O

H H

Rx-ID: 2555802 View in Reaxys 36/75 Yield

Conditions & References With water Abdallah, Hassan; Gree, Rene; Carrie, Robert; Tetrahedron Letters; vol. 23; nb. 5; (1982); p. 503 - 506 View in Reaxys

H N

(S)-2-methylamino-1-phenyl-propanone-(1)

Rx-ID: 7364052 View in Reaxys 37/75 Yield

Conditions & References With water, palladium, Hydrogenation Patent; I.G. Farbenind.; DE639126; (1935); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 23; p. 481 View in Reaxys

O N

H N

Rx-ID: 22222162 View in Reaxys 38/75 Yield

Conditions & References Reaction Steps: 3 1: palladium/charcoal; aqueous methanol. HCl / Hydrogenation 3: NaBH4 With hydrogenchloride, sodium tetrahydroborate, palladium on activated charcoal Takamatsu; Yakugaku Zasshi; vol. 76; (1956); p. 1227; ; (1957); p. 4304 View in Reaxys Reaction Steps: 2 2: palladium/charcoal; acetic acid; HClO4 / Hydrogenation With palladium on activated charcoal, perchloric acid, acetic acid Takamatsu; Yakugaku Zasshi; vol. 76; (1956); p. 1227; ; (1957); p. 4304 View in Reaxys

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H N

salt of (+)-ephedrine

racemate

Rx-ID: 7457746 View in Reaxys 39/75 Yield

Conditions & References With dextrorotatory α-lt;4-arsono-anilinogt;-propionic acid amide, ergibt das Salz des (-)-Ephedrins Fourneau; Nicolitch; Bulletin de la Societe Chimique de France; vol. <4> 43; (1928); p. 1239 View in Reaxys

H N

Rx-ID: 22224125 View in Reaxys 40/75 Yield

Conditions & References Reaction Steps: 2 2: NaBH4 With sodium tetrahydroborate Takamatsu; Yakugaku Zasshi; vol. 76; (1956); p. 1227; ; (1957); p. 4304 View in Reaxys

H N

H 2N

Rx-ID: 97350 View in Reaxys 41/75 Yield

Conditions & References With aluminium Patent; Temmler-Werke; DE871155; (1938) View in Reaxys

H 2N HO

H N

Rx-ID: 437481 View in Reaxys 42/75 Yield

Conditions & References With nickel, acetone, Hydrogenation Patent; I.G. Farbenind.; DE599433; (1930); Fortschr. Teerfarbenfabr. Verw. Industriezweige; vol. 21; p. 691 View in Reaxys

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H N

Rx-ID: 441934 View in Reaxys 43/75 Yield

Conditions & References With palladium on activated charcoal, perchloric acid, acetic acid, Hydrogenation Takamatsu; Yakugaku Zasshi; vol. 76; (1956); p. 1227; ; (1957); p. 4304 View in Reaxys

H N

OH H

Rx-ID: 2659629 View in Reaxys 44/75 Yield

Conditions & References With sodium tetrahydroborate, lithium aluminium tetrahydride, ozone, Multistep reaction. Title compound not separated from byproducts Kashima, Choji; Maruyama, Tatsuya; Fujioka, Yoko; Harada, Kazuo; Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999); (1989); p. 1041 - 1046 View in Reaxys

H N

Rx-ID: 3041990 View in Reaxys 45/75 Yield

Conditions & References With sodium tetrahydroborate, lithium aluminium tetrahydride, other reagents, Product distribution Buckley, Thomas F.; Rapoport, Henry; Journal of the American Chemical Society; vol. 103; nb. 20; (1981); p. 6157 - 6163 View in Reaxys

H 2N HO

H N

OH H N

Rx-ID: 3731677 View in Reaxys 46/75 Yield

Conditions & References With sodium tetrahydroborate, 1.) ether, 0 deg C, 30 min, 2.) from 10 deg C to RT, Yield given. Multistep reaction. Yields of byproduct given. Title compound not separated from byproducts Jackson, W. Roy; Jacobs, Howard A.; Jayatilake, Gamini S.; Matthews, Barry R.; Watson, Keith G.; Australian Journal of Chemistry; vol. 43; nb. 12; (1990); p. 2045 - 2062 View in Reaxys

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H N

H 2N

OH H N H

Si O

Rx-ID: 4693934 View in Reaxys 47/75 Yield

Conditions & References With sodium tetrahydroborate, Yield given. Multistep reaction Effenberger, Franz; Gutterer, Beate; Jaeger, Juergen; Tetrahedron Asymmetry; vol. 8; nb. 3; (1997); p. 459 - 467 View in Reaxys

H N

racemate

Rx-ID: 2198865 View in Reaxys 48/75 Yield

Conditions & References Brown; Moudachirou; Tetrahedron; vol. 50; nb. 34; (1994); p. 10309 - 10320 View in Reaxys Schmid; Wirnsberger; Guebitz; Pharmazie; vol. 51; nb. 11; (1996); p. 852 - 854 View in Reaxys

N-methyl-<l-ephedrine>-hydroxy methylate

H N

Rx-ID: 7364050 View in Reaxys 49/75 Yield

Conditions & References bei der Destillation einer waessr. Loesung Schmidt; Eberhard; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 64,66 View in Reaxys

H 2N

H N

(1S,2R)-1-methylamino-1-phenyl-propan-2-ol (C10H15NO)

Rx-ID: 5497352 View in Reaxys 50/75 Yield

Conditions & References Foltz; Witkop; Journal of the American Chemical Society; vol. 79; (1957); p. 201,203 View in Reaxys Belzecki; Lange; Roczniki Chemii; vol. 28; (1954); p. 561,563, 567, 568; ; (1955); p. 6871 View in Reaxys Belzecki; Lange; Roczniki Chemii; vol. 33; (1959); p. 703,704, 709; ; (1960); p. 2236 View in Reaxys Fourneau; Benoit; Bulletin de la Societe Chimique de France; vol. <5> 12; (1945); p. 985,988 View in Reaxys

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H N

aq.-ethanolic NaOH-solution

Rx-ID: 7989587 View in Reaxys 51/75 Yield

Conditions & References Welsh; Journal of the American Chemical Society; vol. 69; (1947); p. 128,130, 134 View in Reaxys

H H 2N

heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin, complex with (-)-ephedrine

H N

heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin, complex with (R)-1-amino-2-propanol

Rx-ID: 8747023 View in Reaxys 52/75 Yield

Conditions & References in methanol, water, Kinetics Grigorean; Lebrilla; Analytical Chemistry; vol. 73; nb. 8; (2001); p. 1684 - 1691 View in Reaxys

H H 2N

permethylated maltoheptaose, complex with (-)-ephedrine

H N

permethylated maltoheptaose, complex with (R)-1-amino-2-propanol

Rx-ID: 8747024 View in Reaxys 53/75 Yield

Conditions & References in methanol, water, Kinetics Grigorean; Lebrilla; Analytical Chemistry; vol. 73; nb. 8; (2001); p. 1684 - 1691 View in Reaxys

H N

H H HN

Rx-ID: 7545185 View in Reaxys 54/75 Yield

Conditions & References Schmidt,E.; Archiv der Pharmazie (Weinheim, Germany); vol. 246; (1908); p. 217 View in Reaxys Spaeth; Goehring; Monatshefte fuer Chemie; vol. 41; (1920); p. 325 View in Reaxys Schmidt; Archiv der Pharmazie (Weinheim, Germany); vol. 248; (1908); p. 210 View in Reaxys T= 100 °C , Gleichgewicht

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Emde; Helvetica Chimica Acta; vol. 12; (1929); p. 393 View in Reaxys

palladium

H 2N HO

H N

Rx-ID: 7989589 View in Reaxys 55/75 Yield

Conditions & References eines Gemisches.Hydrogenation Freudenberg; Schoeffel; Braun; Journal of the American Chemical Society; vol. 54; (1932); p. 234 View in Reaxys

H N

H HO

Rx-ID: 7991367 View in Reaxys 56/75 Yield

Conditions & References Welsh; Journal of the American Chemical Society; vol. 69; (1947); p. 128,130, 134 View in Reaxys

Cl H HN

barium hydroxide

water

H N

Rx-ID: 7989591 View in Reaxys 57/75 Yield

Conditions & References T= 170 - 180 °C , im Einschlussrohr Spaeth; Goehring; Monatshefte fuer Chemie; vol. 41; (1920); p. 325 View in Reaxys Schmidt; Calliess; Archiv der Pharmazie (Weinheim, Germany); vol. 250; (1912); p. 156; Chem. Zentralbl.; vol. 82; nb. II; (1911); p. 33 View in Reaxys

Br H HN

H N

OH H

Rx-ID: 7545186 View in Reaxys 58/75 Yield

Conditions & References T= 100 °C , wobei das Gleichgewicht nach ca. 280 Stdn. erreicht wird,teils Ersatz von OH durch Br Emde; Helvetica Chimica Acta; vol. 12; (1929); p. 393 View in Reaxys

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N H H

H N

water

Rx-ID: 8470032 View in Reaxys 59/75 Yield

Conditions & References T= 100 °C Emde; Helvetica Chimica Acta; vol. 12; (1929); p. 393 View in Reaxys

–

Na +

N H H

H N

Rx-ID: 534697 View in Reaxys 60/75 Yield

Conditions & References T= 100 °C Emde; Helvetica Chimica Acta; vol. 12; (1929); p. 393 View in Reaxys

amalgamated aluminium HO

aqueous ether

H N

Rx-ID: 7989588 View in Reaxys 61/75 Yield

Conditions & References eines Gemisches.Hydrogenation Patent; Bilhuber Inc.; US1956950; (1931) View in Reaxys Patent; Knoll A. G.; GB360334; (1931) View in Reaxys

H H

H N

I–

water

OH N

N-methyl-<l-ephedrine>

methyl-<β-oxy-α-phenyl-propyl>-<βoxy-β-phenyl-isopropyl>-amine Rx-ID: 8427393 View in Reaxys 62/75

Yield

Conditions & References bei der Destillation Schmidt; Eberhard; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 64,66 View in Reaxys

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H N

water

H HN

OH H

Rx-ID: 8470031 View in Reaxys 63/75 Yield

Conditions & References Emde; Helvetica Chimica Acta; vol. 12; (1929); p. 393 View in Reaxys

H N+

Cl –

water

H H

H N

OH N

methyl-<β-oxy-α-phenyl-propyl>-<βoxy-β-phenyl-isopropyl>-amine

N-methyl-<l-ephedrine>

Rx-ID: 8493234 View in Reaxys 64/75 Yield

Conditions & References bei der Destillation Schmidt; Eberhard; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 64,66 View in Reaxys

H N

Rx-ID: 5673531 View in Reaxys 65/75 Yield

Conditions & References O.N-benzyliden-ephedrine Schmidt; Archiv der Pharmazie (Weinheim, Germany); vol. 252; (1914); p. 99; Chem. Zentralbl.; vol. 84; nb. II; (1913); p. 1310 View in Reaxys

H 2N

O HO

platinum

H N

Rx-ID: 7989590 View in Reaxys 66/75 Yield

Conditions & References eines Gemisches.Hydrogenation Patent; Bilhuber Inc.; US1956950; (1931) View in Reaxys Patent; Knoll A. G.; GB360334; (1931) View in Reaxys

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H H

H N

I–

water

OH OH

N-methyl-<l-ephedrine>

H HO

Rx-ID: 8427391 View in Reaxys 67/75 Yield

Conditions & References bei der Destillation Schmidt; Eberhard; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 64,66 View in Reaxys

H H

H N

I–

sodium amalgam

water

OH OH

N-methyl-<l-ephedrine>

H HO

Rx-ID: 8427392 View in Reaxys 68/75 Yield

Conditions & References Schmidt; Eberhard; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 64,66 View in Reaxys

H N

Cl –

water

H H

H N

OH OH

N-methyl-<l-ephedrine>

H HO

Rx-ID: 8493233 View in Reaxys 69/75

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Yield

Conditions & References bei der Destillation Schmidt; Eberhard; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 64,66 View in Reaxys

O H HN

H N

S OO

Rx-ID: 7991368 View in Reaxys 70/75 Yield

Conditions & References Schmidt; Archiv der Pharmazie (Weinheim, Germany); vol. 252; (1914); p. 121; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 52 View in Reaxys

O H

S OO

H N

H HN

OH H

Rx-ID: 7991369 View in Reaxys 71/75 Yield

Conditions & References Schmidt; Archiv der Pharmazie (Weinheim, Germany); vol. 252; (1914); p. 121; Archiv der Pharmazie (Weinheim, Germany); vol. 253; (1915); p. 52 View in Reaxys

H N

Rx-ID: 7364047 View in Reaxys 72/75 Yield 84%

Conditions & References II. Splitting with ephedrine 35.46 mmoles of racemic acid in solution in 50 ml of ether are placed in a flask. 17.73 mmols of (+) ephedrine in solution in 60 ml of ether are added with continuous stirring. It is left to crystallize at room temperature without stirring. The salt is filtered, washed with ether and dried under vacuum. The salt of the acid is obtained at a yield of 84percent MP=102°-116° C. [α]D 25 =+7.7° (c=1.2, MeOH). Patent; Societe Civile Bioprojet; US5599951; (1997); (A1) English View in Reaxys Mathew et al.; Current Science; vol. 42; (1973); p. 17 View in Reaxys Each of the following compounds exhibited a significant dose- and time-effect, with an interaction of dose and time (all Fs>2.7; all p values <0.01): (+)-amphetamine, (-)-ephedrine, (+)-ephedrine, (-)-norpseudoephedrine, (+)-norpseudoephedrine and

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mephentermine. Patent; Booth, Anthony; Caffrey, James L.; US2003/105332; (2003); (A1) English View in Reaxys More specifically, for example the following compounds can be given as said optically active aminoalcohols. Norephedrine Ephedrine 2-Amino-1-(2-methylphenyl)-1-propanol 2-Amino-1-(2-ethylphenyl)-1-propanol 2-Amino-1-(2-methoxyphenyl)-1-propanol 2-Amino-1-(2-ethoxyphenyl)-1-propanol 2-Amino-1-(2,5-dimethylphenyl)-1-pronanol 2-Amino-1-(2,5-diethylphenyl)-1-propanol 2-Amino-1-(2,5-dimethoxyphenyl)-1-propanol ... Patent; Sumitomo Chemical Company, Limited; US5145998; (1992); (A1) English View in Reaxys (3) Aryl- and heteroaryl ethanolamine derivative, including catecholamine, such as ... etilefrine octopamine synephrine phenylephrine ephedrine orciprenaline isoprenaline dichloroisoprenaline ... Patent; Speiser; Peter; Vaizoglu; M. Orhan; US4810697; (1989); (A1) English View in Reaxys Each of the esters of Examples 1 through 7 is converted to the following illustrative di-amine salts by the procedure of the invention. ammonia ... 2-amino-2-methyl-1-propanol N-methylglucamine ephedrine tetramethylammonium Patent; The Upjohn Company; US3962308; (1976); (A1) English View in Reaxys The optically active amine includes, for example, optically active compounds such as 1-phenyl-2-(p-tolyl)ethylamine, α-(1-naphthyl)-ethylamine, ... erythro- α,β-diphenyl-β-hydroxyethylamine, N-methylephedrine, N-(2,2,2-trichloro-1-formamideethyl)piperidine, 2-benzylamino-1-butanol, ephedrine, cis-N-benzyl-2-(hydroxymethyl)cyclohexylamine, N-(p-hydroxybenzyl)-1-phenylethylamine, N-(p-hydroxybenzyl)-1-(p-tolyl)ethylamine, ... Patent; Sumitomo Chemical Company, Limited; EP933349; (1999); (A1) English View in Reaxys XVIII : Resolution of chlocyphos with (-)-ephedrine and (+)-phencyphos

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EXAMPLE XVIII Resolution of chlocyphos with (-)-ephedrine and (+)-phencyphos To a solution of (-)-ephedrine (2,4 g) in 2-propanol (50 ml) was added (+)-phencyphos (1,75 g) and rac. chlocyphos (1,85 g). The mixture was heated to reflux and allowed to cool to RT. The salt (3,31 g) was treated with 10percent KOH/ toluene. The organic layer was acidified and the solid analyzed with HPLC (6). Both (+)-phencyphos and (+)-chlocyphos were enantiomerically pure (>98percent). Patent; DSM N.V.; US6235927; (2001); (B1) English View in Reaxys The optically active amine includes, for example, optically active compounds such as 1-phenyl-2-(p-tolyl)ethylamine, α-(1-naphthyl)-ethylamine, α-(2-naphthyl)-ethylamine, 1-phenylethylamine, erythro-α,β-diphenyl-β-hydroxyethylamine, N-methylephedrine, N-(2,2,2-trichloro-1-formamideethyl)piperidine, 2-benzylamino-1-butanol, ephedrine, cis-N-benzyl-2-(hydroxymethyl)cyclohexylamine, N-(p-hydroxybenzyl)-1-phenylethylamine, N-(p-hydroxybenzyl)-1-(p-tolyl)ethylamine, N-(p-hydroxybenzyl)-1-(p-isopropylphenyl)ethylamine, N-(p-hydroxybenzyl)-1-(p-nitrophenyl)ethylamine, N-(p-hydroxybenzyl)-1-(p-bromophenyl)ethylamine, ... Patent; Sumitomo Chemical Company, Limited; US6268525; (2001); (B1) English View in Reaxys

ephedrine salt

H N

Rx-ID: 24035769 View in Reaxys 73/75 Yield 98%

Conditions & References 14 : EXAMPLE 14 EXAMPLE 14 Resolution of (R,S)-2-(N-benzyloxycarbonyl)-4-oxo-4-(2'-methoxyphenyl) butyric acid into its enantiomers by crystallization of its diastereoisomeric salt of ephedrine. Dissolve (R,S)-2-(N-benzyloxycarbonylamino)-4-oxo-4-(2'-methoxyphenyl)butyric acid (0.61 g, 1.7 mmoles) in dry ethyl ether (10 ml), warm the obtained solution at 30° C. and add a solution obtained dissolving (-)-Ephedrine (0.300 g, 1.8 mmoles) in dry ethyl ether (25 ml), warm the resulting suspension for 5 min, then cool to room temperature. Filter the precipitate salt and wash it twice with dry ethyl ether to obtain the ephedrine salt as colourless powder (0.87 g,98percent). [α]D 25° C.=-16.25 C (C=0.5,abs.EtOH). Dissolve the obtained salt into ethyl acetate (40 ml), at reflux Temperature, by adding isopropanol (2 ml), then cool the obtained solution at room temperature. After standing at room temperature 72 hours, 0.192 g (44percent) of colourless crystals ([α]D 25° C.=-30.56° C. (C=0.5, abs.EtOH); m.p. 159-161° C.)) are obtained. The mother liquor is evaporated in vacuo to provide a colourless amorphous solid (0.66 9) named solid B. Dissolve the above crystals in warm ethyl acetate (14 ml) and add absolute ethanol (5.5 ml), warm the suspension to reflux for 5 minutes to complete dissolution, then cool to room temperature. After sanding at room temperature 16 hours, 0.113 g of colourless crystals ([α]D 25° C.=-32.0 (C=0.65, abs.EtOH)); m.p. 163°-65° C. are separated. Dissolve the above crystals (0.100 g) in warm ethanol (2 ml) then cool the obtained solution at room temperature. After standing at room temperature 16 hours 0.085 g (20percent) of colourless needles ([α]D 25° C.=-39.9° C. (C=0.1, abs. EtOH); m.p. 166-67° C.)) are separated. 1H-NMR (80 MHz; DMSOd ) ppm: 0.8 (3H, d), 2.5 (3H, s), 3.0-3.4 (3H, m), 3.85 (3H, s), 4.25 (1H, q), 5.0 (2H, s), 6 5.05 (1H, d), 6.9-7.6 (14H, m). C29H34N3O1 Calculated: C 66.70; H 6.56; N 5.36

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Found: C 66.52: H 6.64: N 5.28 Patent; VARASI, MARIO; GIORDANI, ANTONIO; SPECIALE, CARMELA; CINI, MASSIMO; BIANCHETTI, ALBERTO; US2001/8947; (2001); (A1) English View in Reaxys

D-threo-3-(3,4-dibenzyloxyphenyl)-N-pmethoxybenzyloxycarbonylserine

H N

Rx-ID: 25138513 View in Reaxys 74/75 Yield

Conditions & References 2.b : Preparation of L-threo-adrenalinecarboxylic acid (b) The salt of D-threo-3-(3,4-dibenzyloxyphenyl)-N-p-methoxybenzyloxycarbonylserine with (-)-ephedrine (8.6 g) obtained as above was added to a mixture of ethyl acetate (100 ml) and 3N hydrochloric acid (60 ml) to effect extraction of the free acid compound. The ethyl acetate layer separated was washed with 3N hydrochloric acid (60 ml) and then with water (30 ml), and the water-washings were extracted with ethyl acetate (100 ml). The ethyl acetate layers were combined and dried over anhydrous sodium sulfate and concentrated to dryness. The resulting solid residue was recrystallized from a mixture of chloroform and hexane to yield D-threo-3-(3,4-dibenzyloxyphenyl)-N-p-methoxybenzyloxycarbonylserine (6.35 g). Melting point: 130.5°-131.5° C. [α]D 25: +18° (c 0.91, chloroform-methanol=10:1) Elemental analysis: Calculated for C32 H31 NO8: C 68.93, H 5.60, N 2.51percent; Found: C 68.98, H 5.67, N 2.40percent Patent; Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai; US4833268; (1989); (A1) English View in Reaxys

(1R,2S)-ephedrine salt of (S)-6-fluoro-4-ureidochroman-4-carboxylic acid

H N

Rx-ID: 25148013 View in Reaxys 75/75 Yield

Conditions & References 4.A : METHOD A METHOD A A slurry of 35.6 g (0.14 mole) of 6-fluoro-4-ureidochroman-4-carboxylic acid in 1.07 liters of acetone was stirred at reflux (59° C.) for 30 minutes, and then it was cooled to 54° C. To the resulting slurry was added 24.4 g (0.148 mole) of (1R,2S)-ephedrine all in one portion. The slurry thinned and a near solution resulted. After less than two minutes at 55° C. rapid crystallization began. The slurry was refluxed for 2 hours, cooled to 40° C. and the crystalline solid was recovered by filtration to give 26.1 g of the (1R,2S)-ephedrine salt of (S)-6-fluoro-4-ureidochroman-4-carboxylic acid, mp 204 (dec), [alpha]D 25 =+37.0 (c=1, methanol). The mothers liquors were cooled to room temperature and the further solid was recovered by filtration to give 1.3 g of material, mp 180°-185° C. (dec), [alpha]D 25 =0 (C=1, methanol). The filtrate was evaporated in vacuo to give 32.9 g of a mixture of the (1R,2S)-ephedrine salts of (R)-6-fluoro-4-ureidochroman-4-carboxylic acid and (RS)-6-fluoro-4-ureidochroman-4-carboxylic acid, mp 72°-90° C., [alpha]D 25 =-55.7° (C=1, methanol). Patent; Pfizer Inc.; US4551542; (1985); (A1) English View in Reaxys

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