Patent ID: 6372945
Filing Date: 2002-04-16
Classification: C07C,C07D

Abstract:
A process for preparing a compound of the formula wherein:R1 is hydrogen, C1-C4 alkoxy, arylalkoxy, halo, or amino; R2 is hydrogen, C1-C4 alkoxy, arylalkoxy, halo, or amino; and R3 is a thermally-labile or acid-labile C4-C10 alkyl, C4-C10 alkenyl, or aryl(C1-C10 alkyl) group all having a tertiary carbon atom adjacent to the sulfur atom; comprising the steps of: (1) oxidizing a benzyl sulfide of the formula: â€ƒwherein R2 and R3 are as defined above; with an oxidizing agent to produce a benzyl sulfoxide of the formula: â€ƒwherein R2 and R3 are as defined above; (2) reacting said benzyl sulfoxide with a first strong base to form a benzylic anion; (3) condensing said benzylic anion with a benzaldehyde of the formula â€ƒwherein R1 is as defined above; (4) reacting the condensation product from step 3 with an acid chloride to produce an ester of the formula wherein:R1, R2, and R3 are as defined above; and R4 is CO(C1-C6 alkyl), CO(aryl), CO(arylalkyl), SO2(C1-C6 alkyl), SO2(aryl), SO2(arylalkyl), CO2(C1-C6 alkyl), CO2(aryl), CO2(arylalkyl), or CON(C1-C6 alkyl)2; and (5) treating said ester with a second strong base.