几十年来,基于单电子转移使用 Ni 和 Fe 催化剂体系的烷基卤化物和有机金属物种的交叉偶联已被广泛且分别地研究。在这里,我们展示了氧化还原活性酯(从羧酸中分离和原位衍生)与有机锌和有机镁物种的首次偶联,使用最初为烷基卤化物开发的 Fe 基催化剂体系。这项工作通过展示与 Ni 催化剂的直接比较来放置在上下文中,涉及超过 40 个示例,涵盖一系列初级、二级和三级底物。这种新的 C-C 耦合具有可扩展性和可持续性,并且在某些情况下比其基于 Ni 的耦合表现出许多明显的优势。
作者:Pradip K. Maity、Saqib Faisal、Alan Rolfe、Diana Stoianova、Paul R. Hanson
DOI:10.1021/acs.joc.5b01456
日期:2015.10.16
The syntheses of silica-supported oligomeric benzyl phosphates (Si-OBPn) and triazole phosphates (Si-OTPn) using ring-opening metathesis polymerization (ROMP) for use as efficient alkylating reagents is reported. Ease of synthesis and grafting onto the surface of norbornenyl-tagged (Nb-tagged) silica particles has been demonstrated for benzyl phosphate and triazole phosphate monomers. It is shown that these silica polymer hybrid reagents, Si-OBPn and Si-OTPn, can be used to carry out alkylation reactions with an array of different nudeophiles to afford the corresponding benzylated and (triazolyl)methylated products in good yield and high purity.