the reduction of unactivated aryl chlorides and alkyl chlorides in the presence of hydrogen atom donor at room temperature. The catalytic system can also be applied to the coupling of aryl chlorides with electron-rich arene and heteroarenes to affect the C–C bond-forming reactions. Our mechanistic study results support the assumption that carbon radicals are formed from the organochlorides via a sin
Cobalt-Catalyzed Cross-Coupling Reactions of Alkyl Halides with Allylic and Benzylic Grignard Reagents and Their Application to Tandem Radical Cyclization/Cross-Coupling Reactions
Details of cobalt-catalyzed cross-coupling reactions of alkyl halides with allylic Grignard reagents are disclosed. A combination of cobalt(II) chloride and 1,2-bis(diphenylphosphino)ethane (DPPE) or 1,3-bis(diphenylphosphino)propane (DPPP) is suitable as a precatalyst and allows secondary and tertiary alkyl halides--as well as primary ones--to be employed as coupling partners for allyl Grignard reagents
Treatment of alkyl halides, including tertiary alkyl bromides, with benzylic or allylic Grignard reagent in the presence of a catalytic amount of silver nitrate in ether yielded the corresponding cross-coupling products in high yields. The coupling reactions of tertiary alkyl halides provide efficient access to quaternary carbon centers.
Copper-Catalyzed Allylation of Alkyl Halides with Allylic Grignard Reagents
作者:Masahiro Sai、Hideki Yorimitsu、Koichiro Oshima
DOI:10.1246/bcsj.82.1194
日期:2009.9.15
Treatment of alkyl halides, including secondary and tertiary alkyl bromides, with allylic Grignardreagents in the presence of a catalytic amount of copper(II) triflate in diisopropyl ether at 25°C yielded the corresponding allylated products in high yields. The coupling reactions of tertiary alkyl halides lead to construction of allylated quaternary carbon centers. The active species is likely to
在催化量的三氟甲磺酸铜 (II) 存在于二异丙醚中的情况下,在 25°C 下用烯丙基格氏试剂处理烷基卤化物,包括仲和叔烷基溴,以高产率得到相应的烯丙基化产物。叔烷基卤化物的偶联反应导致烯丙基化季碳中心的构建。活性物质可能是烯丙基铜酸盐。
Copper-Catalyzed Reaction of Alkyl Halides with Cyclopentadienylmagnesium Reagent
Treatment of alkyl halides, including tertiary alkyl bromides, with cyclopentadienylmagnesium bromide in the presence of a catalytic amount of copper(II) triflate yielded the corresponding cyclopentadienylated products in high yields. The following hydrogenation of the products provided alkyl-substituted cyclopentanes.