| 摘要 |
PURPOSE: Provided is a novel process for manufacturing the hydroxybenzothiophene of formula(1) comprising cyclocarbonylation of a compound of formula(2). The compound of formula(1) is a building block of pharmaceutically active substances, for example, 5-(4-(2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy)-7-benzothiophenylmethyl)-2,4-thiazolidinedione and the corresponding sodium salt which are from agents useful in the treatment of diabetes. CONSTITUTION: A process for the preparation of bicyclic compound of the formula(1) comprising cyclocarbonylating a monocyclic compound of the formula(2), wherein Y is halogen or -OR; and -OR is an aryloxy group or a group of formulae -O-(CO)-R', -O-(CO)-O-R'' or -O-(PO)-(OR'')2, wherein R' is alkyl, perfluoro-C1-20-alkyl, aryl, R'' is alkyl, aryl or benzyl, by reacting, in an organic solvent medium containing a base and a carboxylic acid anhydride, the monocyclic compound with carbon monoxide in the presence of a carbonylation catalyst capable of complexing with carbon monoxide. The cyclocarbonylation reaction is carried out by introducing carbon monoxide gas into the reaction medium to form the carboxylic acid ester of the compound of formula(1) and thereafter saponifying the ester formed by the carbonylation reaction by treating the ester product in the reaction medium with a base at a pH of from 8 to 14 to form the bicyclic compound.
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