Tandem cyclopropanation with dibromomethane under Grignard conditions

…, L Eberhard, J Oetiker, F Schröder

Index: Brunner, Gerhard; Eberhard, Laura; Oetiker, Juerg; Schroeder, Fridtjof Journal of Organic Chemistry, 2008 , vol. 73, # 19 p. 7543 - 7554

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Citation Number: 10

Abstract

Tertiary Grignard reagents and dibromomethane efficiently cyclopropanate allylic (and certain homoallylic) magnesium and lithium alcoholates at ambient temperature in ether solvents. Lithium (homo) allyl alcoholates are directly cyclopropanated with magnesium and CH2Br2 under Barbier conditions at higher temperatures. The reaction rates depend on the substitution pattern of the (homo) allylic alcoholates and on the counterion with lithium ...