Miscellaneous Methods of Preparing Phosphines

5 Miscellaneous Methods of Preparing Phosphines. Approaches to the synthesis of specific types of organophosphine have been reviewed, covering phosphinoaryloxazolines, /ra j-2,5-disubstituted phospholanes, new chiral phosphines which have been reported since 1990, chiral hydroxyphos-phines, and phosphorus-sulfur donor ligands.The uses of phosphine (PH3) in the synthesis of organophosphines has also been reviewed. A direct route for the synthesis of arylphosphines is offered by the reaction of 

Many new tertiary phosphines have been prepared by synthetic elaboration of simpler organophosphines which does not involve the phosphorus atom. Chiral phosphines bearing heterocyclic substituents have been obtained by elaboration of arylphosphines bearing amino, carboxaldehyde or nitrile groups, respectively, giving, e.g. the pyrrolidinyl system (147), phosphino-oxazolidines, e.g. (148), phosphino-oxathianes, e.g. (149), phos-phino-oxazines (150), and the phosphino-oxazolines (151). Wittig reac- 

Treatment of the phosphino-iminium salts (169) with potassium hydroxide in THF affords the formylphosphines (170), which are remarkably stable in solution compared with the related phosphine oxides Phosphines bearing aminoyl radical substituents, e.g. (171), have also been prepared. The phospha[3]triangulane, (172), has been obtained from the reaction of bicyclo-propylidene with a metal complexed phenylphosphinidene. The phosphino-trithiacyclophane (173) has been prepared by the base-promoted reaction of 

5 Miscellaneous Methods of Preparing Phosphines. - The synthesis and properties of phosphorus-containing cryptand ligands has been reviewed. The basic principles for the synthesis of functionalised phosphorus-containing heterocyclic systems have been summarised, relating to the chemistry of phosphabicyclohexanes, dihydrophosphinines, phosphabicyclooctadienes, and phosphabicyclooctenes °. Ethylene acetals (108) of the 9-oxa-2-phosphabicyclo[4.4.0]-5-one system have been prepared. Methods for the 

Routes to the chiral ferrocenyldiphosphines 113 have been developed, via the use of the chiral oxazaphospholidine borane 114. Routes to other chiral ferrocenylphosphines have also been developed, including the boranato-functio-nalised systems 115, and the C2-symmetric diphosphine 116, having only the planar chirality of the ferrocene system. Full details have now appeared of the palladium-promoted asymmetric Diels-Alder reaction between l-phenyI-3,4-di- 

Full details have now appeared of the stereoselective synthesis of 1,5,9-triphosphacyclododecane systems by oxidative liberation from molybdenum and chromium complexes of the macrocycle, obtained by coordination-template controlled reactionsMolybdenum complexes have also been used in the coordination-template dependent synthesis of the macrocyclic P,S system 151. A non-template synthesis of the 14-membered P2S2 macrocycle, 152, isolated in two isomeric forms, has been described. Halogenation of the cyclometallated phosphine 153 leads to a rearrangement, with the formation of the di-phosphinobiphenyl system 154, from which the free diphosphine can be liberated 

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Miscellaneous Methods of Preparing Phosphines. Palladium-catalysed formation of phosphorus-carbon bonds continues to be developed as a useful route to organophosphines. The reactions of primary or secondary phosphines with aryl- or vinyl-halides in the presence of a palladium catalyst, usually palladium acetate or a zerovalent palladium-phosphine complex, have been used in the synthesis of steroidal phosphines, e.g., (128), the cationic diphosphine system... 

Miscellaneous Methods of Preparing Phosphines. - Transformation of functional groups present in alkyl- and aryl-phosphines has been widely employed in the synthesis of new systems. Further examples of azine formation... 

Miscellaneous Methods of Preparing Phosphines. A review of methods for the preparation of polymer-bound phosphines (and their applications) has... 

Miscellaneous Methods of Preparing Phosphines.- The preparation, and uses in catalysis, of the various types of water-soluble phosphines, have been reviewed. The direct sulphonation of diphos gives a complex mixture of sulphonated products, from which the water-... 

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