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US 6,191,306 B1Granted
Process for the preparation of cyclopropylglycine
AssigneeEastman Chemical Company
InventorsDaniel John Bayston, Jonathan Luke William Griffin, Arne Gruman, Mario Eugenio Cosimino Polywka, Ronald Michael Scott
Life of this patent
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Abstract
Disclosed is a process for the preparation of cyclopropylglycine by a 5-step process wherein cyclopropanecarboxaldehyde is reacted with an α-aminoalkylaromatic compound to obtain an imine which is reacted with a cyanide to produce an aminonitrile compound; the aminonitrile compound is hydrolyzed to the corresponding aminocarboxylic acid and finally the arylalkyl residue is removed from the amino group by hydrogenolysis.
Claims5
Process for the preparation of cyclopropylglycine (CPG) which comprises the steps of:
- (1) contacting cyclopropanecarboxaldehyde with an amine having the formula
- in the presence of a solvent comprising an alkanol, water or a mixture thereof to obtain an imine having the formula:
- (2) contacting the imine of formula (II) with a cyanide selected from alkali metal, alkaline earth metal and trialkylsilyl cyanides in the presence of a solvent comprising an alkanol, water or a mixture thereof to obtain an aminonitrile compound having the formula:
- (3) contacting the aminonitrile compound of formula (III) with a strong acid in the presence of water to obtain an acid addition salt of an aminocarboxylic acid having the formula:
- (4) contacting the acid addition salt of the aminocarboxylic acid of formula (IV) with a hydroxide, carbonate or bicarbonate of an alkali metal or alkaline earth metal in the presence of water to obtain the free aminocarboxylic acid of formula (IV);
- and
- (5) contacting the aminocarboxylic acid of formula (IV) with hydrogen or a hydrogen donor in the presence of a hydrogenation catalyst and an inert solvent to obtain CPG;
- wherein R1 is hydrogen or an alkyl radical;
- and R2 is a carbocyclic aryl radical.
6 more elements
Dependencies are inferred from the claim text.