Process for the preparation of carbapenem antibiotics

Claim 1

A process for preparing a compound having the structure: ##STR105## and the pharmaceutically acceptable salts thereof; wherein R 1 , R 2 , R 6 , R 7 and R 8 are independently selected from the group consisting of hydrogen (R 1 and R 2 are not both hydrogen), substituted and unsubstituted: alkyl, alkenyl, and alkynyl, having from 1-10 carbon atoms; cycloalkyl, cycloalkylalkyl, and alkylcycloalkyl, having 3-6 carbon atoms in the cycloalkyl ring and 1-6 carbon atoms in the alkyl moieties; spirocycloalkyl having 3-6 carbon atoms; phenyl; aralkyl, aralkenyl, and aralkynyl wherein the aryl moiety is phenyl and the alkyl chain has 1-6 carbon atoms; thiophenyl, imidazolyl, tetrazolyl, furyl; thiophenylalkyl, imidazolylalkyl, tetrazolylalkyl and furylalkyl wherein the alkyl moiety contains from 1-10 carbon atoms, and wherein the substituent or substituents relative to the above-named radicals are selected from the group consisting of: amino, mono-, di-, and trialkylamino, hydroxyl, alkoxyl, mercapto, alkylthio, phenylthio, sulfamoyl, amidino, guanidino, nitro, chloro, bromo, fluoro, iodo, cyano and carboxy wherein the alkyl moieties of the above-recited substituents have 1-6 carbon atoms; comprising the steps of treating; ##STR106## with HSR 8 to yield: ##STR107## followed by treating with iodobenzenedichloride to yield: ##STR108## followed by dehydrochlorination in the presence of a strong base at 0° to 6° C., reduction with a reducing agent at -20° to 40° C. and deblocking by hydrogenation in the presence of a catalyst at 0° to 60° C. wherein R° is selected from the group consisting of hydrogen, an alkali metal, nitrobenzyl, tertiary butylbenzyl, trichloroacetoxymethyl, and triloweralkylkammonium.