Ambient Temperature Hydrophosphination of Internal, Unactivated Alkynes and Allenyl Phosphineoxides with Phosphine Borane Complexes
摘要:
Phosphine boranes have been found to hydrophosphinate internal, unactivated alkynes at room temperature under basic conditions without the need for catalysts or radical initiators, The use of air-sensitive secondary phosphines is avoided in this facile process. Broad scope in both the phosphine borane and alkyne partners leads to excellent diversity in the phosphine products. Asymmetric hydrogenation of these species then provides one of the shortest possible routes to chiral monodentate phosphines, Hydrophosphination of allenyl phosphine oxides under similar conditions followed by hydrogenation of the exomethylene moiety yields a wide variety of bis-phosphine derivatives.
Ambient Temperature Hydrophosphination of Internal, Unactivated Alkynes and Allenyl Phosphineoxides with Phosphine Borane Complexes
摘要:
Phosphine boranes have been found to hydrophosphinate internal, unactivated alkynes at room temperature under basic conditions without the need for catalysts or radical initiators, The use of air-sensitive secondary phosphines is avoided in this facile process. Broad scope in both the phosphine borane and alkyne partners leads to excellent diversity in the phosphine products. Asymmetric hydrogenation of these species then provides one of the shortest possible routes to chiral monodentate phosphines, Hydrophosphination of allenyl phosphine oxides under similar conditions followed by hydrogenation of the exomethylene moiety yields a wide variety of bis-phosphine derivatives.
Synthesis of chiral phosphorus compounds from readily available substrates by a facile method is an attractive strategy. In this study, an efficient route for copper-catalyzedasymmetric boroprotonation of phosphinylallenes with bis(pinacolato)diboron with high regioselectivity was developed, affording chiral allylphosphine oxides in high yields with high enantioselectivities of up to 98% ee. The synthetic
通过简便的方法从容易获得的底物合成手性磷化合物是一种有吸引力的策略。在这项研究中,开发了一种铜催化的膦基丙二烯与双(频哪醇)二硼的高区域选择性不对称硼质子化的有效途径,以高产率和高达 98% ee 的高对映选择性提供手性烯丙基氧化膦。通过将手性烯丙基氧化膦轻松转化为几种立体特异性产物,进一步证明了合成效用。
Ambient Temperature Hydrophosphination of Internal, Unactivated Alkynes and Allenyl Phosphineoxides with Phosphine Borane Complexes
作者:Carl A. Busacca、Elisa Farber、Jay DeYoung、Scot Campbell、Nina C. Gonnella、Nelu Grinberg、Nizar Haddad、Heewon Lee、Shengli Ma、Diana Reeves、Sherry Shen、Chris H. Senanayake
DOI:10.1021/ol9022547
日期:2009.12.17
Phosphine boranes have been found to hydrophosphinate internal, unactivated alkynes at room temperature under basic conditions without the need for catalysts or radical initiators, The use of air-sensitive secondary phosphines is avoided in this facile process. Broad scope in both the phosphine borane and alkyne partners leads to excellent diversity in the phosphine products. Asymmetric hydrogenation of these species then provides one of the shortest possible routes to chiral monodentate phosphines, Hydrophosphination of allenyl phosphine oxides under similar conditions followed by hydrogenation of the exomethylene moiety yields a wide variety of bis-phosphine derivatives.