Université de Toulouse, UPS, and CNRS, LHFA UMR 5069, 31062 Toulouse Cedex 9 (France), Fax: (+33) 561558204.
Chemistry. 2014 Jan 3;20(1):297-303. doi: 10.1002/chem.201303039. Epub 2013 Nov 28.
We recently disclosed the synthesis of a novel "push-pull" boryl(phosphino)carbene. To determine the influence of this substitution pattern on the chemical behaviour, a study into the reactivity of the prototype (1) of this new family of B(sp(2))-substituted phosphinocarbenes was undertaken. Carbene 1 exhibits one of the most common intramolecular rearrangements of singlet carbenes, involving a 1,2-mesityl shift, and typical [2+1] cycloaddition reactions with electron-poor acrylonitrile. A pronounced α,β-ambiphilic character was also shown by the reaction of 1 with benzaldehyde, leading to phosphorylalkene 4. Due to its specific electronic properties, carbene 1 also exhibits unprecedented reactivity with chloroacrylonitrile, enabling the formation of bicyclo[1.1.0]phosphetanium salt 6 and borylcyclopropene 9, which have been fully characterised by NMR spectroscopy and X-ray crystallography.
我们最近披露了一种新型“推-拉”硼基（膦基）卡宾的合成。为了确定这种取代模式对化学行为的影响，我们对这种新型 B(sp(2))取代膦卡宾家族的原型（1）进行了反应性研究。卡宾 1 表现出单重态卡宾最常见的分子内重排之一，涉及 1,2-均三甲苯基迁移，以及与缺电子丙烯腈的典型 [2+1]环加成反应。1 与苯甲醛的反应也表现出明显的α,β-两性特征，生成磷酰基烯 4。由于其特殊的电子性质，卡宾 1 还与氯丙烯腈表现出前所未有的反应活性，能够形成双环[1.1.0]膦翁盐 6 和硼基环丙烯 9，它们已通过 NMR 光谱和 X 射线晶体学得到充分表征。
