P-Stereogenic Phosphorus Compounds: Effect of Aryl Substituents on the Oxidation of Arylmethylphenylphosphanes under Asymmetric Appel Conditions
作者:Kamalraj V. Rajendran、Lorna Kennedy、Declan G. Gilheany
DOI:10.1002/ejoc.201000733
日期:2010.10
The effects of aryl ringsubstitution on the dynamic resolution of aryl(methyl)phenylphosphanes under asymmetric Appel reaction conditions have been studied. As expected, substitution at the ortho position strongly affects the degree ofstereoselection that can be achieved. Unexpectedly, however, there was no variation of stereoselectivity with the electronic nature of the para substituents, which suggests
Racemic compounds containing a phosphorus or a sulfur atom as a chiral center were resolved by high-performance liquid chromatography on optically active (+)-poly(triphenylmethyl methacrylate). The resolved compounds include insecticides such as O-ethyl O-(4-nitrophenyl) phenylphosphonothionate (EPN), O-(4-cyanophenyl)-O-ethyl phenylphosphonothionate (cyanofenfos), and 2-methoxy-4H-1,3,2-benzo-dioxaphosphorin
An Efficient Synthesis of α-Iodo Derivatives of Sulfones, Sulfoximines, and Phosphine Oxides
作者:Tsuneo Imamoto、Hiroyasu Koto
DOI:10.1055/s-1985-31415
日期:——
1-Iodoalkyl sulfones are prepared by conversion of alkyl sulfones into 1-sulfonylalkyltriethylalanates by reaction with butyllithium and triethylalane and subsequent reaction with iodine. The same method can be applied to the conversion of methyldiarylphosphine oxides into iodomethyldiarylphosphine oxides and of S-methylsulfoximines into S-iodomethylsulfoximines.
Racemic tertiary phosphines are obtained from dichlorophenylphosphine by a “one pot” synthesis in two steps: (1) condensation of one equivalent of an organocadmium, and (2) substitution of the second chlorine by another organometallic compound.
The title reaction using opticallyactive S-stannylmethyl phosphonothioates, followed by quenching with alkyl iodide affords mainly the corresponding (alkylthiomethyl)phosphineoxides with a retention of configuration.