Cycloalkyl-based chiral auxiliaries and method making the same
US5262571A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1992 |
| Grant date | Nov 16, 1993 |
| Priority date | — |
| Expiry date | Mar 20, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C2601/14
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process of synthesizing enantiomerically pure compounds defined by Formula V, ##STR1## which are useful as chiral auxiliaries is disclosed. The process comprises, first, combining a base of Formula Y.sup.- Z.sup.+ (Formula I), wherein Y.sup.- is an organic anion and Z.sup.+ is an inorganic cation, with a compound of Formula II, ##STR2## wherein R.sub.1 is a C.sub.1 -C.sub.4 alkyl group and R.sub.2 is the same as R.sub.1, or wherein R.sub.1 and R.sub.2 together form cyclopentane or cyclohexane, and wherein R.sub.3 is a substituted or unsubstituted aryl group, to form a compound defined by Formula III, ##STR3## then: (b) reacting the compound of Formula III with a cyclic epoxide defined by Formula IV, ##STR4## wherein n is 1, 2, or 3, to form a racemic mixture of a compound defined by Formula V. ##STR5## In a preferred embodiment, the method further comprises stereospecifically esterifying one of the enantiomers of the racemic mixture of compound (V) and a carboxylic acid with an enzyme in an organic solvent, wherein said acid is a C.sub.2 -C.sub.20 alkyl acid, benzoic acid or a C.sub.2 -C.sub.14 alkyl benzoic acid, and then separating the esterified enantiomer from the non-esterif…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.