摘要：

The reaction of aldehydes or ketones with allyl halides/Zn takes place readily in aqueous NH{sub 4}Cl solution in the presence of C-18 silica as a solid organic cosolvent. This efficient and high-yield reaction parallels the Grignard reaction in terms of stereo- and regioselectivity. There are two applications, however, where this process has special advantages. The formation of the Grignard reagent with dimethylallyl halides is plagued by coupling side products while our aqueous cases react smoothly. Another advantage is that the reaction can be carried out without the protection of additional hydroxy functional groups. A diverse selection of examples are presented, and a potential mechanism is discussed.

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