Free Radical Chain Reactions of [1.1.1]Propellane with Three-Coordinate Phosphorus Molecules. Evidence for the High Reactivity of the Bicyclo[1.1.1]pent-1-yl Radical
作者:Kevin P. Dockery、Wesley G. Bentrude
DOI:10.1021/ja962287z
日期:1997.2.1
Three-substituted bicyclo[1.1.1]pent-1-yl radicals (5), generated from additions of radicals to [1.1.1]propellane (1), are found to have high propensities to react with three-coordinate phosphorus molecules. For example, the 3-ethylbicyclo[1.1.1]pent-1-yl radical (5d) reacts with (EtO)3P in a free-radical Arbuzov process to yield dimethyl 3-ethylbicyclo[1.1.1]pent-1-ylphosphonate (13). By contrast
三取代的双环[1.1.1]戊-1-基自由基(5),由自由基加成到[1.1.1]丙烷(1)产生,被发现具有与三配位磷分子反应的高倾向。例如,3-乙基双环[1.1.1]戊-1-基自由基(5d)在自由基Arbuzov过程中与(EtO)3P反应生成3-乙基双环[1.1.1]戊-1-基膦酸二甲酯(13). 相比之下,乙基自由基不与 (EtO)3P 反应生成 EtP(O)(OEt)2。然而,高度反应性的苯基自由基会产生 PhP(O)(OEt)2。此外,正戊基双环[1.1.1]戊-1-基自由基(5b)对n-C5H11P(OMe)2的攻击导致自由基取代过程,产生二甲基3-正戊基[1.1.1 ]双环戊基-1-基亚膦酸酯(7b)和伯烷基n-C5H11•。因此,5具有与三配位磷键合的倾向,该倾向大于伯烷基基团的键合倾向并且与苯基基团的键合倾向相似。发现 2-benzyl-4-methyl-1,3,2-dioxaphospholane