Azadibenzophospholes: Functional Building Blocks with Pronounced Electron-Acceptor Character
摘要:
A series of azadibenzophospholes with varying location of the nitrogen center has been synthesized and comprehensively characterized. In the context of the study, suitably brominated phenylpyridine precursors were accessed via Suzuki-Miyaura cross-coupling for the first time. Despite being nonfluorescent, X-ray crystallographic studies of two azadibenzophosphole oxides revealed planar conjugated scaffolds with high degree of pi-conjugation. The P-oxidized species were found to show desirable reversible reduction features that support promising electron-accepting properties of the materials. The presence of the nitrogen as well as phosphorus centers within the scaffold allowed for further functionalization with transition metals, as well as methyl groups that result in altered absorption and redox features for the materials. Subsequent bromination of the scaffold selectively occurred at the exocydic P-phenyl group, as confirmed via X-ray crystallography. This halogenation allowed for further modification of the system via catalytic cross-coupling with pyridine.
Azadibenzophospholes: Functional Building Blocks with Pronounced Electron-Acceptor Character
摘要:
A series of azadibenzophospholes with varying location of the nitrogen center has been synthesized and comprehensively characterized. In the context of the study, suitably brominated phenylpyridine precursors were accessed via Suzuki-Miyaura cross-coupling for the first time. Despite being nonfluorescent, X-ray crystallographic studies of two azadibenzophosphole oxides revealed planar conjugated scaffolds with high degree of pi-conjugation. The P-oxidized species were found to show desirable reversible reduction features that support promising electron-accepting properties of the materials. The presence of the nitrogen as well as phosphorus centers within the scaffold allowed for further functionalization with transition metals, as well as methyl groups that result in altered absorption and redox features for the materials. Subsequent bromination of the scaffold selectively occurred at the exocydic P-phenyl group, as confirmed via X-ray crystallography. This halogenation allowed for further modification of the system via catalytic cross-coupling with pyridine.
Palladium-Catalyzed Direct Synthesis of Phosphole Derivatives from Triarylphosphines through Cleavage of Carbon-Hydrogen and Carbon-Phosphorus Bonds
作者:Katsuaki Baba、Mamoru Tobisu、Naoto Chatani
DOI:10.1002/anie.201307115
日期:2013.11.4
(Phosp)hole in one: A palladium‐catalyzed synthesis for directly assembling phosphole skeletons fromtriarylphosphinesthrough CH and CP bond cleavage was developed. This approach overcomes several of the limitations of the so far reported methods. Phospholes bearing a range of functionalities (including Br, F, CO2Me, Ac, and CN) and an array of fused rings (naphthalenes, anthracenes, furans, and
在一个(Phosp)孔:一个钯催化合成的用于从至C三芳基膦直接组装磷杂环骨架 H和13 C P键裂解被开发。这种方法克服了迄今为止报道的方法的一些局限性。可以容易地合成具有一系列功能性(包括Br,F,CO 2 Me,Ac和CN)的磷脂和一系列稠环(萘,蒽,呋喃和吡咯)。