Selective C–P(O) Bond Cleavage of Organophosphine Oxides by Sodium
摘要:
Sodium exhibits better efficacy and selectivity than Li and K for converting Ph3P(O) to Ph2P(OM). The destiny of PhNa co-generated is disclosed. A series of alkyl halides R4X and aryl halides ArX all react with Ph2P(ONa) to produce the corresponding phosphine oxides in good to excellent yields.
The controllable phosphorylations of thioesters were developed. When the reaction was catalyzed by a palladium catalyst, aryl or alkenyl phosphoryl compounds were generated through decarbonylative coupling, while the benzyl phosphoryl compounds were produced through deoxygenative coupling when the reaction was carried out in the presence of only a base.
Palladium-Catalyzed C–P Bond-Forming Reactions of Aryl Nonaflates Accelerated by Iodide
作者:Holly McErlain、Leanne M. Riley、Andrew Sutherland
DOI:10.1021/acs.joc.1c02172
日期:2021.12.3
iodide-accelerated, palladium-catalyzed C–P bond-forming reaction of aryl nonaflates is described. The protocol was optimized for the synthesis of aryl phosphine oxides and was found to be tolerant of a wide range of aryl nonaflates. The general nature of this transformation was established with coupling to other P(O)H compounds for the synthesis of aryl phosphonates and an aryl phosphinate. The straightforward
complexes as transition metal catalysts provided a variety of organophosphorus compounds from readily available aryl and vinyl halides, as well as aryl triflates, with generally a good-to-excellent reaction efficiency (31 examples, 46%-98% yields). The current protocol features mild reaction conditions, a broadsubstratescope, recyclability of photocatalysts, and inexpensive catalysts, thus defining the practical
Herein, NiCl2 was employed as a cheap precatalyst in the formation of C(sp2)-P bond via cross coupling reaction of phenol derivates and phosphine oxides/phosphites. This method allows a variety of phenols with diverse functional groups to transform to phosphates with good yields. No additional additive was used in this reaction.
Oxidative C–C/P–H cross-coupling is achieved via Pd-catalyzed decarbonylative cross-coupling of aroylhydrazides with P(O)H compounds. The unique cooperative reaction system, especially the Brønsted acid and bidentate phosphine ligand, allows the selective activation of the inert C–C bond and the suppression of the undesired oxidation and coordination of >P(O)–H compounds, leading to a general oxidative
氧化的C / C / P-H交叉偶联是通过Pd催化的酰肼与P(O)H化合物的脱羰交叉偶联而实现的。独特的协同反应系统,特别是布朗斯台德酸和双齿膦配体,可以选择性活化惰性碳键,并抑制> P(O)–H化合物的不希望的氧化和配位,从而导致一般的氧化反应从容易获得的底物中合成芳基磷化合物。