Synthesis and Characterization of R2PNP(iBuNCH2CH2)3N: A New Bulky Electron-Rich Phosphine for Efficient Pd-Assisted Suzuki−Miyaura Cross-Coupling Reactions
摘要:
Pro-azaphosphatrane 1a [P((BuNCH2CH2)-Bu-i)(3)N] reacts with iodine under mild conditions to give [IP((BuNCH2CH2)-Bu-i)(3)N]I in excellent yield, which on subsequent reaction with ammonia followed by deprotonation with (KOBu)-Bu-t provided HN=P((BuNCH2CH2)-Bu-i)(3)N (3a) in quantitative yield. Reaction of 3a with R'2PCl afforded sterically bulky electron-rich phosphines of the type R'2PN=P((BuNCH2CH2)-Bu-i)(3)N (4) [R' = Ph (4a), Pr-i (4b), Bu-t (4c)]. The Pd(OAc)(2)/4c catalyst system was particularly efficient for the coupling of arylboronic acids with aryl bromides as well as aryl chlorides to give biaryls in excellent yields.
(<i>t</i>-Bu)<sub>2</sub>PNP(<i>i</i>-BuNCH<sub>2</sub>CH<sub>2</sub>)<sub>3</sub>N: New Efficient Ligand for Palladium-Catalyzed C−N Couplings of Aryl and Heteroaryl Bromides and Chlorides and for Vinyl Bromides at Room Temperature
作者:Ch. Venkat Reddy、Jesudoss V. Kingston、John G. Verkade
DOI:10.1021/jo702367k
日期:2008.4.1
chlorides possessing base-sensitive substituents (nitro, ester, and keto) provide coupling products with bulky aryl amines in good to excellent yields. Aryl halides possessing other functional groups including cyano, amino, trifluoromethyl, and phenol, coupled with equal ease, producing highly functionalized amines in good to excellent yields. Moreover, an aryl chloro group can be preserved in the presence
Synthesis and Characterization of R<sub>2</sub>PNP(<sup>i</sup>BuNCH<sub>2</sub>CH<sub>2</sub>)<sub>3</sub>N: A New Bulky Electron-Rich Phosphine for Efficient Pd-Assisted Suzuki−Miyaura Cross-Coupling Reactions
作者:Jesudoss V. Kingston、John G. Verkade
DOI:10.1021/jo062452l
日期:2007.4.1
Pro-azaphosphatrane 1a [P((BuNCH2CH2)-Bu-i)(3)N] reacts with iodine under mild conditions to give [IP((BuNCH2CH2)-Bu-i)(3)N]I in excellent yield, which on subsequent reaction with ammonia followed by deprotonation with (KOBu)-Bu-t provided HN=P((BuNCH2CH2)-Bu-i)(3)N (3a) in quantitative yield. Reaction of 3a with R'2PCl afforded sterically bulky electron-rich phosphines of the type R'2PN=P((BuNCH2CH2)-Bu-i)(3)N (4) [R' = Ph (4a), Pr-i (4b), Bu-t (4c)]. The Pd(OAc)(2)/4c catalyst system was particularly efficient for the coupling of arylboronic acids with aryl bromides as well as aryl chlorides to give biaryls in excellent yields.