Halophosphines

Preparation and Properties of Organophosphines. AUphatic phosphines can be gases, volatile Hquids, or oils. Aromatic phosphines frequentiy are crystalline, although many are oils. Some physical properties are Hsted in Table 14. The most characteristic chemical properties of phosphines include their susceptabiUty to oxidation and their nucleophilicity. The most common derivatives of the phosphines include halophosphines, phosphine oxides, metal complexes of phosphines, and phosphonium salts. Phosphines are also raw materials in the preparation of derivatives, ie, derivatives of the isomers phosphinic acid, HP(OH)2, and phosphonous acid, H2P(=0)0H. 

Halophosphines can be reduced to phosphines. Various methods have been employed to recover the product, but yields are only fair. Triphenylphosphine [603-35-0] is prepared from ben2ene and phosphoms trichloride ... 

In general, if the desired carbon—phosphoms skeleton is available in an oxidi2ed form, reduction with lithium aluminum hydride is a powerful technique for the production of primary and secondary phosphines. The method is appHcable to halophosphines, phosphonic and phosphinic acids as well as thein esters, and acid chlorides. Tertiary and secondary phosphine oxides can be reduced to the phosphines. 

Halophosphines can be treated with organometaUic reagents, eg, Grignard reagents, organomercuries, and organolithiums, to produce tertiary phosphines. 

Primary and secondary phosphines can be treated with halogenating agents to produce halophosphines. 

Tertiary phosphines and primary and secondary phosphines can be oxidized by elemental halogen to halophosphine halides. 

Organophosphinates (90) may also be prepared by the oxidation of secondary phosphines or halophosphines with hydrogen peroxide or sulfur ... 

Reactions of halophosphines with conjugated heterodienes leading toP,0-, P,N-, and P,N,0-heterocycles 99UK167. 

Reduction of halophosphines [34-37] or alkyl phosphonates [38] using lithium aluminum hydride is commonly employed for the preparation of alkyl or aryl substituted primary phosphines (Eqs. 1-4) ... 

See related HALOPHOSPHINES, NON-METAL AZIDES, NON-METAL HALIDES... 

See other halophosphines, iodine compounds, non-metal halides... 

Data from this laboratory and others8,9,10 indicate that the general procedure outlined for the synthesis of F2PX compounds may be extended to the synthesis of the oxy derivatives of pentavalent phosphorus such as F2C1P0 and Cl2FPO, but the detailed directions are not given here. The mixed oxyhalides of phosphorus, like the corresponding mixed halophosphines, have not been obtained easily in pure form from complex reaction mixtures.11,12... 

Halophosphazenes, 19 56 Halophosphine halides, 19 65 Halophosphines, 19 61, 65 IV-Halophthalimides, 13 109 Halopredone acetate, 4 359t Haloprogesteron, 4 360t Halo-pyrimidine-based dyes, 9 475... 

HALOBORANES, A-HALOGEN COMPOUNDS HALOPHOSPHINES, HALOSILANES PERFLUOROSILANES... 

ALKYLHALOPHOSPHINES, ALKYLPHOSPHINES tert-BUTYL PEROXOPHOSPHATE ESTERS iV-CHLORINATED PHOSPHORUS AMIDES HALOPHOSPHINES, METAL PHOSPHINATES METAL PHOSPHORUS TRISULFIDES NON-METAL OXIDES, NON-METAL SULFIDES PHOSPHINES, PHOSPHORUS ESTERS... 

The reaction of a diphosphine with a dihalo compound, resulting in the formation of a di- or tetra-phosphonium salt2c, is a special case because if fits well with a cyclization on phosphorus, but also at the same time with a cyclization between two chains already linked to the second phosphorus (reaction 102). Another kind of ring closure on the phosphorus results from the biphilic character of halophosphines toward dienic392 or acetylenic28,393 systems (reaction 105). 

See other HALOPHOSPHINES, IODINE COMPOUNDS, NON-METAL HALIDES 4633. Titanium tetraiodide... 

Xenon difluoride, 4326 Xenon difluoride oxide, 4313 Xenon hexafluoride, 4371 Xenon tetrafluoride, 4347 HALOBORANES N-HALOGEN COMPOUNDS HALOPHOSPHINES HALOSILANES PERFLUOROSILANES... 

Chromophores based on aryl moieties can be easily grafted on to halophosphines via simple nucleophilic substitutions, as illustrated by the synthesis of 114 (Scheme 4.34). As a result, numerous phosphines bearing extended jt-conjugated substituents have been prepared. The aim of this section is not to give a comprehensive account of all derivatives that have been synthesized, but rather to illustrate how phosphorus fragments can be used either to influence or to organize the Jt-conjugated systems, with special emphasis upon fluorescence and NLO properties. 

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