Kalviri Hassan A, Gärtner Felix, Ye Gang, Korobkov Ilia, Baker R Tom
Department of Chemistry and Centre for Catalysis Research and Innovation (CCRI) , University of Ottawa , 10 Marie Curie , Ottawa , Ontario K1N 6N5 , Canada . Email:
Leibniz-Institut für Katalyse (LIKAT) , Albert-Einstein Straβe 29a , 18059 Rostock , Germany.
Chem Sci. 2015 Jan 1;6(1):618-624. doi: 10.1039/c4sc02710h. Epub 2014 Oct 30.
While thermolysis of ammonia-borane (AB) affords a mixture of aminoborane- and iminoborane oligomers, the most selective metal-based catalysts afford exclusively cyclic iminoborane trimer (borazine) and its B-N cross-linked oligomers (polyborazylene). This catalysed dehydrogenation sequence proceeds through a branched cyclic aminoborane oligomer assigned previously as trimeric B-(cyclodiborazanyl)amine-borane (BCDB). Herein we utilize multinuclear NMR spectroscopy and X-ray crystallography to show instead that this key intermediate is actually B-(cyclotriborazanyl)amine-borane (BCTB) and a method is presented for its selective synthesis from AB. The reactivity of BCTB upon thermal treatment as well as catalytic dehydrogenation is studied and discussed with regard to facilitating the second dehydrogenation step in AB dehydrocoupling.
虽然氨硼烷（AB）的热解会产生氨基硼烷和亚氨基硼烷低聚物的混合物，但最具选择性的金属基催化剂仅生成环状亚氨基硼烷三聚体（硼嗪）及其B-N交联低聚物（聚硼氮烯）。这种催化脱氢序列通过一种支链环状氨基硼烷低聚物进行，该低聚物先前被指定为三聚体B-（环二硼氮烷基）胺硼烷（BCDB）。在此，我们利用多核核磁共振光谱和X射线晶体学表明，这个关键中间体实际上是B-（环三硼氮烷基）胺硼烷（BCTB），并提出了一种从AB选择性合成它的方法。研究并讨论了BCTB在热处理以及催化脱氢时的反应性，以促进AB脱氢偶联中的第二步脱氢。
