2,2′-diborabiphenyl:: A Lewis acid analogue of 2,2′-bipyridine
2,2′-diborabiphenyl:: A Lewis acid analogue of 2,2′-bipyridine
复制标题
DOI：
10.1002/anie.200390320
复制
发表时间：
2003-01-01
影响因子：
16.6
通讯作者：
Parvez, M
中科院分区：
文献类型：
--
作者：
Emslie, DJH;Piers, WE;Parvez, M
螯合刘易斯碱作为刘易斯酸性过渡金属的配体是必不可少的化学工具，而2，2 '-联吡啶家族的配体（I）是其中最重要的。[1]相反，作为阴离子中心或双官能刘易斯碱的反向配体的螯合刘易斯酸不太常见。[2]鉴于I作为双齿配体的成功，我们对其硼类似物II作为阴离子和中性刘易斯碱的潜在螯合刘易斯酸产生了兴趣。虽然前者有望用于制备新型阴离子杂环化合物和过渡金属的硼杂联苯配体，[3]使用中性双官能氮刘易斯碱可以导致B2 N2二硼芳烃加合物，其与全碳多环芳烃（PAH）等电子。[4]虽然多环芳烃是探测芳香性的基本兴趣，[5]最近对多环芳烃的兴趣源于材料化学的潜在应用。[6]B2 N2类似物很可能表现出与其母体烃明显不同的光学和氧化还原性质，因为这种结构固有的极化。在这里，我们报告的合成一些刘易斯碱加成物的衍生物II，包括双官能哒嗪供体，这导致新的杂环类似物的多环芳烃，包含一个{C2 B2 N2}核心。
Chelating Lewis bases are indispensable chemical tools as ligands for Lewis acidic transition metals, and the 2, 2’-bipyridine family of ligands (I) is among the most important.[1] Conversely, chelating Lewis acids that act as reverse ligands for anionic centers or bifunctional Lewis bases are less common.[2] Given the success of I as a bidentate ligand, we became interested in its boron analogue II as a potential chelating Lewis acid towards anionic and neutral Lewis bases. While the former holds promise for preparing novel anionic heterocycles and boratabiphenyl ligands for transition metals,[3] use of neutral bifunctional nitrogen Lewis bases could lead to B2N2 diboraarene adducts which are isoelectronic with all-carbon polycyclic aromatic hydrocarbons (PAHs).[4] Although PAHs are of fundamental interest for probing aromaticity,[5] recent interest in PAHs stems from potential applications in materials chemistry.[6] B2N2 analogues would, in all likelihood, exhibit optical and redox properties that are markedly different from their parent hydrocarbons, because of the polarization inherent to such structures. Herein we report the synthesis of some Lewis base adducts of a derivative of II that includes bifunctional pyridazine donors, which lead to novel heterocyclic analogues of polycyclic aromatic hydrocarbons that contain a {C2B2N2} core.