Isolation and structure of bis(2,2′-biphenylylene)dichloro- and -difluoropertelluranes, [12-Te-6(C4X2), X = Cl, F] (λ6-tellane)
摘要:
Bis(2,2'-biphenylylene)tellurane (1; lambda(4)-tellane) reacts with sulfuryl chloride and xenon difluoride to give bis(2,2'-biphenylylene)dichloro-and -difluoropertelluranes, [12-Te-6(C4X2), X = Cl (2a), F (2b)] (lambda(6)-tellane) in high yields. The structures of the pertelluranes 2a and 2b were determined by single crystal X-ray crystallographic analysis, revealing that they have a distorted octahedral geometry and a cis-configuration with respect to the coordinated halogen atoms, and subsequently each was analyzed by an ab initio calculation. (C) 1997 Elsevier Science Ltd.
A synthesis of tellurium-embedded π-extended aromatics from tellurium powder and readily available cyclic diaryliodonium salts has been developed. The versatility of this method has been demonstrated by the synthesis of various functionalized dibenzotellurophenes (DBTe's), a ladder-type π-system, and a heterosumanene. These compounds demonstrated good air/moisture stability and high thermal stability
Chalcogen- and Halogen-Bond-Donating Cyanoborohydrides Provide Imine Hydrogenation
作者:Mikhail V. Il’in、Yana V. Safinskaya、Denis A. Polonnikov、Alexander S. Novikov、Dmitrii S. Bolotin
DOI:10.1021/acs.joc.3c02282
日期:2024.3.1
telluronium and iodonium cyanoborohydrides provide a significantly higher rate of the model reaction of imine hydrogenation compared with sodium and tetrabutylammonium cyanoborohydrides. Based on the NMR and high-resolution electrospray ionization mass spectrometry data indicating that the reaction progress is accompanied by the cation reduction, a mechanism involving intermediate formation of elusive onium
锍、硒、碲和碘氰基硼氢化物已被合成、分离,并通过各种方法(包括单晶 X 射线衍射 (XRD) 分析)充分表征。基于X射线衍射数据的分子中原子量子理论分析表明,在每种化合物的晶体结构中观察到的氢化物·σ-空穴短接触具有纯非共价性质。与氰基硼氢化钠和四丁基铵氰基硼氢化物相比,碲和碘氰基硼氢化物提供显着更高的亚胺氢化模型反应速率。基于核磁共振和高分辨率电喷雾电离质谱数据表明反应进程伴随着阳离子还原,提出了一种涉及难以捉摸的氢化鎓中间体形成的机制,作为亚胺部分传统亲电活化的替代方案。连接至阳离子的 σ-孔。
Access to Valuable Chalcogen-Containing Biaryl Derivatives via Regioselective 2,2′-Dichalcogenation of 2-Bromobiaryls
The regioselective installation of chalcogen atoms into biaryl scaffolds is an important synthetic task due to the great value of chalcogen-containing biaryl derivatives in many fields. Here we undertake this task by developing a regioselective2,2′-dichalcogenation of 2-bromobiaryls with common chalcogen sources using an organolanthanum-mediated one-pot, two-step protocol. This strategy features high