Preparing Amides

problem with this reaction is that the secondary amine is still nucleophilic so that a mixture of amines in various states of alkylation result, including the quaternary salt compound, which binds to the halide in a salt. This can be demonstrated in figure 106:

Figure 106.

This is similar to starting with ammonia and adding an alkyl group via an alkyl halide. The process just keeps on alkylating the nitrogen group.

PREPARING AMIDES

There are a couple of ways to make an amide compound, which is a carbonyl group attached to an R chain and a nitrogen group. It can first be done through an acid chloride molecule, which is an RCOCl molecule—a molecule that can be seen as able to add an acyl group (an RCO group) to a nitrogen compound (an amine) in basic conditions, yielding an amide. A second way is through the addition of an amine to an acid anhydride, also under basic conditions. How these can be done is shown in figure 107:

Figure 107.