Direct coupling of functionalized organolithium compounds with aryl and vinyl halides
摘要:
The reaction between beta- and gamma-nitrogen-functionalized and gamma- and epsilon-oxygen-functionalized organolithium compounds 3, 4, 30-32 and different aromatic, heteroaromatic, and vinylic halides affords directly the corresponding substitution products: functionalized benzamides 5-26 and alcohols 33-37. Symmetrical and mixed products of double coupling 38-40 were also prepared from 1,4-diiodobenzene. The formation of alkyl halides as intermediates has been verified. Aryl or vinyl halides giving rise to unstable aryl or vinyllithium reagents were unsuccessful in the coupling reaction.
Not borrowed: A new method was developed for the cross‐coupling of two different alcohols (see scheme). This carbon–carbonbondformation was realized by using a small amount of CuBr (0.05–0.2 mol %) and NaOH (4–20 mol %) in the presence of H2 (1 atm), and provides an alternative procedure for longer‐chain alcohols. The catalytic cycle was different from those reported to date for the Guerbet reaction
β‐Alkylation through Dehydrogenative Coupling of Primary Alcohols and Secondary Alcohols Catalyzed by Thioether‐Functionalized N‐Heterocyclic Carbene Ruthenium Complexes
Cationic Ru(II)(η6-p-cymene) complexes of hybrid NHC ligands (imidazole and benzimidazole-based) featuring a thioether moiety were noted to be good catalysts for β-alkylation of secondaryalcohols with primary alcohols.
具有硫醚部分的杂化NHC配体(基于咪唑和苯并咪唑)的阳离子Ru(II)(η 6 - p -伞花烃)络合物被认为是仲醇与伯醇β-烷基化的良好催化剂。