一系列基于甲巯咪唑的软蝎形阴离子([RTmMe]–,R = H,Ph,Me,nBu)在桥头硼处进行取代,已被用于生产一系列通式为 [Ge(RTmMe)2 的锗配合物]I2。通过 X 射线晶体学对锗配合物的结构分析表明,它们都包含八面体 S6 配位球。已经通过热重分析研究了蝎形阴离子(作为它们的 Li 或 Na 盐)和它们的锗配合物。该分析表明游离的蝎形阴离子的降解途径不同于复合物的降解途径。这两种途径都涉及一个甲巯咪唑环的丢失,从而支持在热侵蚀条件下可以发生硼-氮键断裂的观点。正如预期的那样,锗的存在改变了阴离子的降解曲线。与游离阴离子相比,四种复合物都显示出类似的降解机制。尽管锗的存在促使阴离子的构象发生变化,但它的存在并没有显着增加硼 - 氮键的稳定性。
Polycondensed Heterocycles. Part 11: Preparation and Regioselective Reductions of 5-Phenyl-4H-pyrrolo[1,2-a][1]benzazepin-4-one
摘要:
The Wadsworth-Emmons olefination between 2-(1H-pyrrol-1-yl)benzaldehyde and methyl alpha-(diethylphosphonyl)phenyl acetate leads exclusively to the cis-isomer of methyl 2-(1H-pyrrol-1-yl)-alpha -phenylcinnamate, which, after transformation into the corresponding acid chloride, was easily cyclised to the title enone. This latter was regioselectively reduced to the corresponding saturated ketone or unsaturated alcohol, under different experimental conditions. An improved preparation of starting 2-(1H-pyrrol-1-yl)benzaldehyde is also reported. (C) 2000 Elsevier Science Ltd. All rights reserved.
leads to the assembly of polymer chains through multiple Lewispairing in their backbone. These new polyboramines are dihydrogen reservoirs that can be used for the hydrogenation of imines and carbonyl compounds. They also display a unique dihydrogen thermal release profile that is a direct consequence of the insertion of the amine–borane linkages in the polymericbackbone.