Cyclization towards Carbon-Carbon Double Bond. III. A New Synthesis of 1-Pyrroline Derivatives and a Synthesis of 1, 2-Dialkyl-3-diphenyl-methlenepyrrolidine Alkyl Halide, an Anti-acetylcholine Substance

• Published in: Chemical & pharmaceutical bulletin Vol. 14; no. 2; pp. 187 - 193
• Main Authors: Ohki, Sadao, Hamaguchi, Fumiko, Yanagi, Tokuko, Yoshino, Motoyo
• Format: Journal Article
• Language: English
• Published: Tokyo The Pharmaceutical Society of Japan 1966; Japan Science and Technology Agency
• ISSN: 0009-2363; 1347-5223
• DOI: 10.1248/cpb.14.187

2-Subsituted 3-diphenylmethylene-1-pyrrolines (III) were synthesized in one step by the reaction of 1, 1-diphenyl-1, 4-butanediol (VII), 2, 2-diphenyltetrahydrofuran (VI), or 4-bromo-1, 1-diphenyl-1-butene (V) with nitrile-stannic chloride complex. 2, 5-Dimethyl (XI) and 2, 5, 5-trimethyl-3-diphenylmethylene-1-pyrroline (XII) were obtained respectively from 1, 1-diphenyl-1, 4-pentanediol (IX) and 1, 1-diphenyl-4-methyl-1, 4-pentanediol (X). The fact that 2-methyl-3-isopropylidene-1-pyrroline (XIV) was obtained from 2-methyl-2, 5-pentanediol (XIII) and 2, 2-dimethyltetrahydrofuran (XV) by the same reaction was of interest in contrast with preparation of 1-pyrrolines (II) by the Ritter reaction. Reduction of the methiodide of III with sodium borohydride gave 1-methyl-2-alkyl-3-diphenylmethylenepyrrolidine. The methiodide of the 2-methyl compound (XVIc) was found to have a comparatively strong anti-acetylcholine activity.