Conventional Lithium Bases as Unconventional Sources of Methyl Anion: Facile Me−Si and Me−C Bond Cleavage in RLi, R<sub>2</sub>NLi, and BR<sub>4</sub><sup>-</sup> by an Electrophilic Osmium Dihydride
作者:Dmitry V. Yandulov、John C. Huffman、Kenneth G. Caulton
DOI:10.1021/om0200104
日期:2002.9.1
and compete for the Os with, the original base, the unsaturated silicon species formed by Si−Me cleavage react with the remaining base by 1,2-addition of (N,C)-Li, forming intermediates that are also reactive by β-Me- transfer. A complex mixture of Os-free coproducts is obtained in both cases. The structural features of 1+ responsible for its unusual reactivity are discussed.
顺式,反式-Os(H)2(OTf)(NO)(P i Pr 3)2(1-OTf)和Os(H)2(NO)(P i Pr 3)的其他几种前体(1-X))2 +(1 +)与(ME反应3 Si)的2 NLi等,(ME 3 Si)的2 CHLi,锂2,2,6,6-四甲基(TMPLi)中,Me 3 SICH 2 Li和B(CH 2森达3)4 -由一个极不寻常的,轻便β-ME -转移,对于在非极性溶剂的前两个专属的反应途径。已经检验了一系列烷基锂和烷基酰胺和有机硼酸试剂以显示直接β-R的普遍发生“ -转移(R” = H,Me)的给OS电体,是用于完全选择性β-H -在β-我-,唯一(令人惊讶的)NpLi例外。的β-R“消除被排除作为净β-R的机构” -转移为两个代表性的RLi例R” = H,Me和单电子转移机理被证明是不起作用为tetraalkylborates。机理研究还揭示了Li在RLi和R 2 NL