Studies on the Azasteroids and Related Compounds. V. Syntheses of Isomeric Ethyl 3-Methoxy-2-piperidineacetates and 4-Methoxy-1, 2, 3, 4, 4a, 5, 7, 8, 9, 10-Decahydro-6H-benzo[c]-quinolizin-6-ones

Abstract

The lactim ether (XXII), prepared from 3-methoxy-2-piperidone (XXI) by the action of Meerwein reagent, condensed smoothly with benzyl cyanoacetate to give the Cope product (XXIII), which underwent debenzylation and decarboxylation, followed by sodium borohydride reduction and alcoholysis, yielding a mixture of ethyl cis- and trans-3-methoxy-2-piperidineacetates (XXIX). Cyclodehydration of XXIX with cyclohexanone afforded the vinylogous amides (XXX).