Experiments on the synthesis of santonin. III. The preparation and bromination‐dehydrobromination of ethyl α‐(2:3:4:5:6:7:8: 10‐octahydro‐1: 10‐dimethyl‐2‐oxo‐7‐naphthyl)propionate

Abstract

Mukherjee'sl preparation of ethyl a-(4-methyl-3-oxocyclohexyl)propionate has been improved.Condensed with I-diethylaminopentan-3-one this affords ethyl a-(2 : 3 : 4 : 5 : 6 : 7 : 8 : 10octahydro-1 : lO-dirnethyl-2-oxo-7-naphthyl)propionate, the bromination4ehydrobromination of which has k e n studied. I-Chloro-and I-diethylamino-pent-I-en-3-one are described for the first time. Attempts t o condense these compounds with 2-methylcyclohexanone and with ethyl a-(4-methyl-3-oxocyclohexyl)propionate were unsuccessful.