15849-86-2Relevant academic research and scientific papers
A simple resolution procedure using the Staudinger reaction for the preparation of P-stereogenic phosphine oxides
Andersen,Ramsden,Che,Parvez,Keay
, p. 7478 - 7486 (2007/10/03)
The resolution of a variety of (±)-P-stereogenic phosphines is achieved by exploiting the Staudinger reaction of a (±)-phosphine with enantiopure (1S,2R)-O-(tert-butyldimethylsilyl)isobornyl-10-sulfonyl azide. The resulting mixtures of diastereomeric phosphinimines are generally separable by fractional crystallization or flash chromatography. Subsequent acid-catalyzed hydrolysis provides the corresponding optically pure phosphine oxides in high yields.
Conformational Preference in 1,3-Dithianes Containing 2-Phosphoryl, -(thiophosphoryl), and -(selenophosphoryl) groups. Chemical and Crystallographic Implications of the Nature of the Anomeric Effect
Mikolajczyk, Marian,Graczyk, Piotr P.,Wieczorek, Michal W.
, p. 1672 - 1693 (2007/10/02)
The operation of anomeric effect in all the title compounds studied was found.The magnitude of the anomeric effect was found to be larger than 10 kJ/mol.Crystallographic, spectroscopic, and thermodynamic data suggest that nS-?*C
Synthesis and Properties of Mixed Substituted (Chloroacetyl)organylphenylphosphanes
Lindner, Ekkehard,Merkle, Ralf Dieter,Mayer, Hermann August
, p. 645 - 658 (2007/10/02)
The mono-, di- and trichloroacetylorganylphenylphosphanes X1X2CClC(O)PPhR (3av-cz) are obtained by reaction of Me3SiPPhR (2v-z) with the azid chlorides X1X2CClC(O)Cl (1a-c).Increasing content of chlorine results in a shift of the >C=O band and the 31P signal to higher wavelengths and fields, respectively, in the IR and 31P NMR spectra of 3av-cz.Due to the centre of chirality at the phosphorus atom in the 1H NMR spectra one observes diastereotopic protons in the chloroacetyl moiety of 3av-az and of the P-adjacent CH2 protons of 3aw-cw and 3ay-cy.The magnetic inequivalence of both methyl substituents in the isopropyl groups of 3ax-cx is observable also in the 13C and 1H NMR spectra.Because of steric reasons the free rotation about the P-isopropyl axis is hindered up to 355 K.From the coalescence temperature the free activation energy ΔG* is calculated to give 74.7 kJ/mole.The degradation of the thermolabile compounds 3av-cz results in the formation of the chlorophosphanes 5v-z.Individual investigations on 3bv, 3bw and 3by indicate the formation of mono- and dichloroacetyl chloride.The appearance of ClCH2C(O)Cl proceeds via the chloroketene 4b.
DARSTELLUNG UND NMR-SPEKTROSKOPISCHE CHARAKTERISIERUNG EINIGER DI-n-ALKYL- UND n-ALKYLARYL-CHLOROPHOSPHANE
Wolfsberger, W
, p. 167 - 174 (2007/10/02)
A series of di-n-alkyl and n-alkylaryl chlorophosphines has been prepared by the reaction of tetraorganodiphosphines with chlorodiphenyl or dichlorophenyl phosphine and characterized by 31P and 13C NMR spectra.
SYNTHESE DIRECTE DE PHOSPHINES TERTIARIES RACEMIQUES ET DE CHLOROPHOSPHINES DISSYMETRIQUES
Chodkiewicz, W.,Guillerm, D.,Jore, D.,Mathieu, E.,Wodzki, W.
, p. 107 - 114 (2007/10/02)
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 phosphines liberated from the resulting complexes can be stabilised by direct complexation with cuprous salts.The monochlorophosphines can be isolated in the first stage when their cadmium complexes are submitted to ligand exchange with pyridine.
Reactions with Phosphine Alkylenes, XLI. Resolution of Chiral Phosphonium Salts
Bestmann, Hans Juergen,Lienert, Juergen,Heid, Eckard
, p. 3875 - 3879 (2007/10/02)
The preparation and resolution of chiral phosphonium salts 1a - c via the corresponding phosphonium ylides is described.
