Perry Griffin L, Schley Nathan D
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States.
J Am Chem Soc. 2023 Mar 29;145(12):7005-7010. doi: 10.1021/jacs.3c00885. Epub 2023 Mar 15.
Tris(bicyclo[1.1.1]pentyl)phosphine can be prepared by radical addition of PH to [1.1.1]propellane, giving the smallest tri--alkylphosphine known. PBcp is substantially smaller than PCy and is comparable in electron-donating power to PEt. It gives a bis-ligated Pd(0) complex Pd(PBcp) that is exceptionally reactive toward alkyl halide oxidative addition and functions as a general ligand for palladium-catalyzed cross-coupling of sp electrophiles. Radical addition of [1.1.1]propellane to phenylphosphine gives the bis(bicyclo[1.1.1]pentyl)phosphine derivative PBcpPh, illustrating the generality of this approach to bicyclopentylphosphine synthesis.
三（双环[1.1.1]戊基）膦可通过将PH自由基加成到[1.1.1]丙搭烯上制备，得到已知最小的三烷基膦。PBcp比PCy小得多，给电子能力与PEt相当。它能形成双配位的Pd(0)配合物Pd(PBcp)，该配合物对卤代烷氧化加成反应具有异常高的活性，并且作为钯催化的sp亲电试剂交叉偶联反应的通用配体。将[1.1.1]丙搭烯自由基加成到苯膦上可得到双（双环[1.1.1]戊基）膦衍生物PBcpPh，这说明了这种合成双环戊基膦方法的通用性。
