Maar Ryan R, Hoffman Nicholas A, Staroverov Viktor N, Gilroy Joe B
Department of Chemistry and The Centre for Advanced Materials and Biomaterials Research, The University of Western Ontario, 1151 Richmond Street North, London, Ontario, N6A 5B7, Canada.
Chemistry. 2019 Aug 22;25(47):11015-11019. doi: 10.1002/chem.201902419. Epub 2019 Jul 8.
The synthesis of compounds containing multiple bonds to boron has challenged main-group chemists for decades. Despite significant progress, the possibility that the formation of such bonds can turn on photoluminescence has received minimal attention. We report an oxoborane (B=O) complex that is electronically stabilized by a formazanate ligand in the absence of significant steric bulk and, unlike the common BX (X=F, Cl) formazanate adducts, exhibits intense photoluminescence. The latter property was rationalized through density-functional calculations which indicated that the B=O bond enhances photoluminescence by drastically reducing differences between the ligand's geometries in the ground and excited states. The title oxoborane compound was synthesized from an air- and moisture-stable BCl formazanate complex and subsequently converted to a redox-active boroxine. Each of these species may also serve as a precursor to functional materials.
几十年来，含硼多键化合物的合成一直是主族化学家面临的挑战。尽管取得了重大进展，但此类键的形成能开启光致发光的可能性却很少受到关注。我们报道了一种氧硼烷（B=O）配合物，在没有显著空间位阻的情况下，它通过甲脒配体实现电子稳定，并且与常见的BX（X=F、Cl）甲脒加合物不同，它表现出强烈的光致发光。通过密度泛函计算对后者的性质进行了合理化解释，结果表明B=O键通过大幅降低配体在基态和激发态的几何结构差异来增强光致发光。标题氧硼烷化合物由一种对空气和湿气稳定的BCl甲脒配合物合成，随后转化为具有氧化还原活性的硼氧六环。这些物质中的每一种也都可以用作功能材料的前体。
