Dibenzothiepin Derivatives and Related Compounds. IV. Reactions of Various Cyclic Ketones including 6, 11-Dihydrodibenzo-[b, e] thiepin-11-ones with SbCl5

• Published in: YAKUGAKU ZASSHI Vol. 98; no. 10; pp. 1341 - 1348
• Main Authors: HORI, MIKIO, KATAOKA, TADASHI, SHIMIZU, HIROSHI, ONOGI, KAZUHIRO
• Format: Journal Article
• Language: Japanese
• Published: The Pharmaceutical Society of Japan 25.10.1978
• Subjects: 6, 11-dihydrodibenzo [b, e] thiepin-11-ones; 6-chloro-6, 11-dihydrodibenzo [b, e]-thiepin-11-one; bis [2-(2-formylbenzoyl) phenyl] disulfide; hydrogen bonding; ketone-SbCl5 (1 : 1) adduct; protonation product of ketone; ring-opening reaction
• ISSN: 0031-6903; 1347-5231
• DOI: 10.1248/yakushi1947.98.10_1341

In order to examine the reaction of 6, 11-dihydrodibenzo [b, e] thiepin-11-ones (21) and antimony pentachloride, reaction of various ketones with SbCl5 or HCl-SbCl5 was carried out. Tricyclic ketones (1a-d) gave the corresponding protonation products (9a-d) but monocyclic ketones, such as diphenylcyclopropenone (13) and γ-pyrone (19) only formed ketone-SbCl5 adducts (1 : 1) (12, 18) with SbCl5 and protonation products (14, 20) with HCl-SbCl5. Stereochemical considerations were made on the formation mechanism of these products. Reaction of 6, 11-dihydrodibenzo [b, e] thiepin-11-one (21) with SbCl5 gave the anticipated protonation product (22) but that of 6-chloro-6, 11-dihydrodibenzo [b, e] thiepin-11-one (5) and SbCl5 resulted in cleavage of the thiepin ring, contrary to expectations, and a compound (23) of undetermined structure was obtained. This compound (23) transited to bis [2-(2-formylbenzoyl) phenyl] disulfide (24) by hydrolysis.