Lu Wei, Li Yongxin, Ganguly Rakesh, Kinjo Rei
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, and ‡NTU-CBC Crystallography Facility, Nanyang Technological University , 637371, Singapore.
J Am Chem Soc. 2017 Apr 12;139(14):5047-5050. doi: 10.1021/jacs.7b02251. Epub 2017 Mar 28.
A 2,3-dihydro-1H-1,2-azaborole derivative 2 was converted to a cyclic (alkyl) (amino)carbene (cAAC) via 1,2-hydrogen migration triggered by boranes to afford cAAC-borane adducts. This procedure allowed us to develop an asymmetrical diborene cAAC·(Br)B═B(Br)·IDip 6, which was isolated and fully characterized. The B NMR spectrum, X-ray diffraction analysis and computational studies indicate that π-electrons on the central B moiety in 6 are unequivalently distributed, and thus polarized. A complete scission of the B═B double bond in 6 was achieved by the treatment with an isonitrile, which led to the formation of a base-stabilized B,N-containing methylenecyclopropane 7.
一种2,3-二氢-1H-1,2-氮杂硼烷衍生物2通过硼烷引发的1,2-氢迁移转化为环状（烷基）（氨基）卡宾（cAAC），得到cAAC-硼烷加合物。该方法使我们能够开发出一种不对称二硼烯cAAC·(Br)B═B(Br)·IDip 6，它被分离出来并进行了全面表征。硼核磁共振谱、X射线衍射分析和计算研究表明，6中中心硼部分的π电子分布不均等，因此发生了极化。通过用异腈处理，实现了6中B═B双键的完全断裂，导致形成了一种碱稳定的含硼、氮的亚甲基环丙烷7。
