Preparation of E-(2-substituted-1-methylethylidene)indanones derived from monic acid
摘要:
Alkylation of the lithium dienolate of the monic acid hydroxamate (3) with o-bromo(bromomethyl) benzene or heteroaromatic derivatives gave alpha-alkylated products (5). This alkylation procedure wa surprisingly catalysed by 4-dimethylaminopyridine. Metal-halogen exchange with t-butyl lithium occurred with concomitant intramolecular cyclisation to give a mixture of the deconjugated ketones (6). Reconjugation with potassium t-butoxide stereoselectively produced with the E-isomer (7). Deprotection gave the monic acid derived ketone (1).
Preparation of E-(2-substituted-1-methylethylidene)indanones derived from monic acid
摘要:
Alkylation of the lithium dienolate of the monic acid hydroxamate (3) with o-bromo(bromomethyl) benzene or heteroaromatic derivatives gave alpha-alkylated products (5). This alkylation procedure wa surprisingly catalysed by 4-dimethylaminopyridine. Metal-halogen exchange with t-butyl lithium occurred with concomitant intramolecular cyclisation to give a mixture of the deconjugated ketones (6). Reconjugation with potassium t-butoxide stereoselectively produced with the E-isomer (7). Deprotection gave the monic acid derived ketone (1).