(E)-Selective olefination of aldehydes by means of gem-dichromium reagents derived by reduction of gem-diiodoalkanes with chromium (II) chloride

T Okazoe, K Takai, K Utimoto

Index: Okazoe, Takashi; Takai, Kazuhiko; Utimoto, Kiitiro Journal of the American Chemical Society, 1987 , vol. 109, # 3 p. 951 - 953

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Citation Number: 168

Abstract

3 aldehyde because of the following limitations:(i) low reactivity of the geminal dimetallic compounds (Mtl= BS or AI6);(ii) lack of stereoselectivity of the products; 5bs6c (iii) side reactions such as the reduction of a carbonyl group'or reductive coupling of an aldehyde to al, 2-dioL7 Recently, Knochel and Normant reported that 1-magnesium 1-zinc compounds add to aldehydes with the assistance of BF3. 0Et2 to give olefins with good E selectivity. 8 ...