季全碳中心的构筑一直是有机合成中的难点和热点,其中以廉价三级溴代烷为原料,通过分子间C(sp3)—C(sp3)键形成来合成该类季全碳中心更是鲜有报道.采用廉价锌粉作为还原性自由基引发剂,诱导三级溴代烷形成叔碳自由基,进而实现用烯烃捕获该自由基的策略来高效构筑C(sp3)—C(sp3)键季全碳中心.
The construction of the quaternary carbon center has been a difficult and hot issue in organic synthesis.In particular, the synthesis of quaternary carbon center by the formation of the intermolecular C(sp3)—C(sp3)bond with cheap tert-alkyl bromides is rarely reported.Recently, our group reported that nickel-catalyzed reductive coupling of aryl bromides with tertiary alkyl halides.Based on this, we proposed that using cheap reductive metal as a free radical initiator, mediated the formation of tertiary carbon free radicals from tert-alkyl bromides, and then the free radical captured by olefin to build C(sp3)—C(sp3)bond quaternary carbon center efficiently.Herein, we report the application of this strategy in constructing quaternary carbon center by Zn powder mediated reductive coupling reaction.
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