Preparation of chiral amides and amines
This invention provides a convenient method for converting oximes into enamides. The process does not require the use of metallic reagents. Accordingly, it produces the desired compounds without the concomitant production of a large volume of metallic waste. The enamides are useful precursors to amides and amines. The invention provides a process to convert a prochiral enamide into the corresponding chiral amide. In an exemplary process, a chiral amino center is introduced during hydrogenation through the use of a chiral hydrogenation catalyst. In selected embodiments, the invention provides methods of preparing amides and amines that include the 1,2,3,4-tetrahydro-N-alkyl-1-naphthalenamine or 1,2,3,4-tetrahydro-1-naphthalenamine substructure.
1. A mixture of 1,2,3,4-tetrahydronaphthalenamines consisting of:
wherein:
R 4 is a member selected from substituted or unsubstituted aryl and substituted or unsubstituted heteroaryl;
Q − is an anion;
e and f are independently selected numbers from 0 to 1; and
wherein A is present in said mixture in a ratio of 90:10 to 98:2 relative to B1 and B2.
2. A mixture according to claim 1 wherein R 4 is
3. A mixture according to claim 2 wherein X 1 and X 2 are both chlorine.