Synthesis and characterization of some p-methylphosphetanes, a new class of electron-rich chiral phosphines
作者:Angela Marinetti、Louis Ricard
DOI:10.1016/s0040-4020(01)80558-5
日期:1993.1
phosphetane oxides 4 and 6 are prepared either by starting from (methyl)PCl2 and an appropriate olefin, or by reacting (methyl)MgCl with a 1-chlorophosphetane. Highly selective alkylation and halogenation reactions of the corresponding anions 4′ afford α-substituted derivatives in diastereomerically pure form. Reductions of the phosphetane oxides with HSiCl3.Et3N proceed with retention of configuration about
A Phosphetane Catalyzes Deoxygenative Condensation of α-Keto Esters and Carboxylic Acids via P<sup>III</sup>/P<sup>V</sup>═O Redox Cycling
作者:Wei Zhao、Patrick K. Yan、Alexander T. Radosevich
DOI:10.1021/ja511889y
日期:2015.1.21
A small-ring phosphacycle is found to catalyze the deoxygenative condensation of α-keto esters and carboxylic acids. The reaction provides a chemoselective catalytic synthesis of α-acyloxy ester products with good functional group compatibility. Based on both stoichiometric and catalytic mechanistic experiments, the reaction is proposed to proceed via catalytic P(III)/P(V)═O cycling. The importance
Reactions of 1-substituted 2,2,3,4,4-pentamethylphosphetans with hexafluoroacetone and the 19F nuclear magnetic resonance spectra of the resulting 1,3,2-dioxaphospholans
作者:Robert K. Oram、Stuart Trippett
DOI:10.1039/p19730001300
日期:——
with hexafluoroacetone. The 19F n.m.r. spectra of these adducts over a range of temperatures have given values of the free energies of activation for the pseudorotation processes which place the four-membered ring diequatorial and the 1-substituents apical. The variation in these activation energies with the nature of the 1-substituent is accounted for in terms of the relativeapicophilicity of groups
已经制备了一系列的1-取代的2,2,3,4,4-五甲基膦酸酯,并且在用六氟丙酮处理后将其转化为相应的1,3,2-二氧杂膦酸酯。这些加合物在一定温度范围内的19 F nmr光谱给出了伪旋转过程的活化自由能值,该伪旋转过程使四元环二甲基吡咯和1位取代基位于顶峰。在与1-取代基的性质这些活化能的变化在组既是电负性和的函数的相对apicophilicity方面占p π - d π背键。探索了该假设的一些后果。描述了1,3,2-二氧杂磷杂环戊烷和相关的1,2-氧杂磷杂环戊烷的一些不寻常的反应和异构化。
ORGANIC PHOSPHORUS COMPOUNDS 106.<sup>1</sup> A <sup>31</sup>P-NMR STUDY OF PHOSPHINOUS-, PHOSPHINIC-, AND THIOPHOSPHINIC AMIDES
作者:Ludwig Maier、Peter J. Diel
DOI:10.1080/10426509608037973
日期:1996.8.1
Abstract The synthesis, physical, chemical and spectroscopic properties of eight different types of phosphinous-, phosphinic- and thiophosphinic amides are reported. It is shown that the 31P-chem. shifts of tertiary amides are at lower magnetic field than that of secondary amides. As an exception, in the bis(tertiary butyl) series this trend is reversed.