US 5,442,117 AGranted

Enantiomeric resolution

AssigneeAlbemarle Corporation

InventorsG. Patrick Stahly, Thanikavelu Manimaran

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Abstract

A process for obtaining a substantially pure enantiomer of an hydrocarbyl amine is described. The process utilizes first an enantiomerically enriched mixture the of hydrocarbyl amine obtained from kinetic resolution, diastereomeric crystallization or asymmetric synthesis processes. This enriched mixture is reacted with an inorganic acid producing a salt that has the following properties: 1) has at least one eutectic point; 2) a composition that is not at the eutectic point; and 3) a eutectic composition that is closer to the racemic composition than is the eutectic composition of said hydrocarbyl, or be a solid where the salt is a liquid. A substantially pure, enantiomeric salt is separated, leaving a mother liquor comprising the solvent and the hydrocarbyl amine enriched in the other enantiomer.

Claims16

Dependent claims

A process for producing a substantially pure enantiomeric salt of a hydrocarbyl amine having the formula:

##STR4## where R.sub.1 and R.sub.2 are different and are hydrogen, alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, substituted naphthyl;
R.sub.3, R.sub.4 and R.sub.5 are different and are hydrogen, alkyl, cycloalkyl, phenyl, naphthyl, substituted phenyl, substituted naphthyl, haloalkyl, hydroxyalkyl, alkoxyalkyl, acyloxyalkyl, carboxyalkyl, alkoxycarbonylalkyl or cyanoalkyl;
and n is 0 or 1;
which comprises:
i) reacting said hydrocarbyl amine enriched with one of its enantiomers with an optically inactive acid thereby forming a salt of said hydrocarbyl amine enriched with said enantiomer, said salt having:
a) at least one eutectic point;
b) a composition that is not at the eutectic point;
and c) a eutectic composition that is closer to the racemic composition than is the eutectic composition of said hydrocarbyl amine, or be a solid where compound I is a liquid;
ii) treating said salt with an inert solvent;
iii) separating a salt of the substantially pure enantiomer of the hydrocarbyl amine.

7 more elements

Dependencies are inferred from the claim text.