Ethynyldimesitylborane (1) is synthesised via salt elimination and its reactivity towards NHCs is studied. Depending on their size, NHCs attack either at the boron atom or at the β-alkynyl carbon atom. Steric control over the reaction was probed by reactions with N-heterocyclic carbenes yielding a carbene–borane adduct (2), a 1-boraindane (3), and the first structurally characterised borataallene (4).
通过消盐法合成了
乙炔基二甲酰
硼烷 (1),并对其与 NHC 的反应活性进行了研究。根据其大小,NHC 要么攻击
硼原子,要么攻击β-炔基碳原子。通过与 N-杂环碳氢化合物反应生成碳烯-
硼烷加合物 (2)、1-
硼印烷 (3) 和首个结构上定性的
硼达烯 (4),对反应的立体控制进行了探究。