Electrophilic Sulfides (II) as a Novel Catalyst. V. Structure, Nucleophilicity, and Steric Compression of Stabilized Sulfur Ylides as Observed by 13 C-NMR Spectroscopy

H Matsuyama, H Minato, M Kobayashi

Index: Matsuyama,H. et al. Bulletin of the Chemical Society of Japan, 1977 , vol. 50, p. 3393 - 3396

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Citation Number: 10

Abstract

13 C chemical shifts and 13 C–H spin coupling constants (179.7 Hz) of the ylide carbons of two dialkylsulfonium phenacylides show that the ylide carbons are basically sp 2. Large upfield shifts (− 9.5–− 11.8 ppm) of carbonyl carbon signals (δ C 181.7 and 179.2) of the ylides from those of the corresponding salts (δ C 191.2 and 191.0) suggest significant contribution of a betaine structure. The 13 C-NMR spectrum of methylisopropylsulfonium ...