Patent ID: 7220562

Claim:
A process for producing (E)-2-methyl-2-butenoic acid and (Z)-2-methyl-2-butenoic acid in high yield and purity from a mixture of (E,Z)-2-methyl-2-butenenitriles comprising (a) contacting a mixture of (E,Z)-2-methyl-2-butenenitriles in a suitable aqueous reaction mixture with a catalyst expressing nitrile hydratase and amidase activities and selected from the group consisting of Comamonas testosteroni 5-MGAM-4D (ATCC 55744), Comamonas testosteroni S2B-1 (ATCC PTA-5135), and Comamonas testosteroni S5C (ATCC PTA-5134); (b) separating the (E)-2-methyl-2-butenoic acid produced in step (a) in the form of a salt or acid from (Z)-2-methyl-2-butenamide and unreacted (Z)-2-methyl-2-butenenitrile; and (c) treating the (Z)-2-methyl-2-butenamide and unreacted (Z)-2-methyl-2-butenenitrile from step (b) with a suitable catalyst or chemical reagent to produce (Z)-2-methyl-2-butenoic acid in the form of a salt or acid.