Mechanistic aspects of thiyl radical-promoted acyl radical cyclization of formylenoate-cyclization versus oxidation

K Yoshikai, T Hayama, K Nishimura…

Index: Yoshikai, Kazuya; Hayama, Tomoharu; Nishimura, Katsumi; Yamada, Ken-Ichi; Tomioka, Kiyoshi Chemical and Pharmaceutical Bulletin, 2005 , vol. 53, # 5 p. 586 - 588

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Citation Number: 4

Abstract

Treatment of formylalkenoates 1 and 7 with 2, 2′-azobis (2-methylpropanenitrile)(AIBN) in the presence of dioxygen gave oxygenated carboxylic acids 5, 6, 8, 9 instead of acyl radical cyclization products, through preferential reaction of the corresponding acyl radicals with dioxygen rather than intramolecular attack to an enoate moiety. The reaction of 1 with AIBN in the absence of dioxygen recovered starting 1 in 98% yield.