Diborane(4) compounds with bidentate diamino groups†
Abstract
The reaction between B2(NMe2)4 and 1,2-(NH2)2-4-ButC6H3 affords the diborane(4) compound 1,2-B2{1,2-(NH)2-4-ButC6H3}2 as the exclusive product whilst the reaction between rac-1,2-(NH2)2C6H10 and B2(NMe2)4 also affords only the 1,2-isomer, i.e.1,2-B2{1,2-(NH)2C6H10}2, which is shown to be the more stable isomer by computational methods. The previously reported compounds 1,1-B2{1,2-(NH)2C6H4}2 and 1,2-B2{1,2-(NH)2C6H4}2 both react with four equivalents of BunLi to give what are presumed to be tetra-anions which react further with MeI, SnClMe3 or SnClPh3 to give the tetrasubstituted products 1,1-B2{1,2-(NMe)2C6H4}2, 1,1-B2{1,2-(NSnMe3)2C6H4}2 and 1,2-B2{1,2-(NSnPh3)2C6H4}2 respectively. The compound 1,1-B2{1,8-(NH)2C10H6}2 has also been prepared from the reaction between B2(NMe2)4 and