B-Methylated Amine-Boranes: Substituent Redistribution, Catalytic Dehydrogenation, and Facile Metal-Free Hydrogen Transfer Reactions
作者:Naomi E. Stubbs、André Schäfer、Alasdair P. M. Robertson、Erin M. Leitao、Titel Jurca、Hazel A. Sparkes、Christopher H. Woodall、Mairi F. Haddow、Ian Manners
DOI:10.1021/acs.inorgchem.5b01946
日期:2015.11.16
dehydrogenation chemistry of amine-boranes substituted at nitrogen has attracted considerable attention, much less is known about the reactivity of their B-substituted analogues. When the B-methylated amine-borane adducts, RR′NH·BH2Me (1a: R = R′ = H; 1b: R = Me, R′ = H; 1c: R = R′ = Me; 1d: R = R′ = iPr), were heated to 70 °C in solution (THF or toluene), redistribution reactions were observed involving
尽管在氮上取代的胺-硼烷的脱氢化学引起了相当大的关注,但对它们的B-取代的类似物的反应性知之甚少。当B-甲基化胺-硼烷加合物时,RR'NH·BH 2 Me(1a:R = R'= H; 1b:R = Me,R'= H; 1c:R = R'= Me; 1d:R = R'= i Pr),在溶液(THF或甲苯)中加热到70°C,观察到重新分布反应,包括硼上甲基和氢取代基的明显扰乱,提供了RR'NH·BH的混合物3– x Me x(x= 0–3)。推测这些反应是通过胺-硼烷离解,然后可逆地形成乙硼烷中间体和加合物重整而发生的。Dehydrocoupling的1A - 1D在THF与铑(I),铱(III)和Ni(0)的预催化剂在20℃下导致的制品阵列,包括氨基硼烷RR'N═BHMe,环状diborazane [RR'N- BHMe] 2和硼嗪[RN–BMe] 3基于原位11 B NMR光谱分析,并通过