Alkyl fluorophosphines

A. Preparation.—Halogen displacement reactions have been used to prepare a number of new aminofluorophosphines. Aminodifluorophos-phine (1) has been prepared for the first time, from either bromodifluoro-phosphine or chlorodifluorophosphine, and ammonia. Studies of its n.m.r. spectrum have been made (see Chapter 11). The related NN-difluoroaminodifluorophosphine (2) has been prepared, from difluoroiodo-phosphine, and found to be explosive. Two syntheses of A-alkyl-amino-difluorophosphines have been reported, one of which was complicated by the subsequent formation of the phosphorane (3) and the bis-(A-alkylamino)fluorophosphine (4). 

PtCl2(PPh3)2] with hydrazine or alcoholic KOH in the presence of excess phosphine. A very wide range of similar complexes with alkyl-, alkaryl-, and fluorophosphines as well as with phosphites is now known. [Pt(PPh3)4] dissociates readily in solution by sequential loss of PPh3 (see equation 1). 

Alkyl and aryl fluorophosphines, R PF3. (R = hydrocarbon group n = 1,2) are known to undergo spontaneous redox disproportionation in accord with... 

III. Fluorophosphines Containing Phosphorus-Carbon Bonds. Alkyl- or Arylfluorophosphines, R PF8 . ... 

Although the direct reaction between alkyl- or aryldichlorophos-phines and h fdrogen fluoride only produces 10-15% yields of aryldi-fluorophosphines and no isolable alkyl derivatives 84), treatment of the intermediate products of the reaction with tertiary amines significantly increases the yields (30-35%, R = aryl 15-20%, R = alkyl). 

Oxidation of trifluorophosphine by halogens is well known (282) and although corresponding reactions with alkyl or aryl fluorophosphines have received only little attention, it has become apparent that oxidation to the pentavalent phosphorus fluorides can be brought about by a wide variety of reagents. In certain cases the reducing property of the fluoro-phosphine has been utilized in the synthesis of zero-valent transition metal fluorophosphine complexes (Section IX). 

Bisdimethylaminofluorophosphine and alkyl- or aryldialkylamino-fluorophosphines can also be readily oxidized by halogens (86)... 

Tetelbaum et al. (315) have suggested that a correlation exists between Sp for compounds of the type XPF2 (where the group X is alkyl, aryl, or halogenoalkyl) and the Taft a parameter for X. While it is true that the lowest-fleld chemical shifts (—200 to —250 ppm) occur for the alkyl derivatives, values for other fluorophosphines sometimes show irregular variations (Tables II-VI) even within fairly closely related compounds. 

Chromium(I) complexes, 702 alkyl isocyanides, 704-709 aryl isocyanides, 704-709 2,2 -bipyridyl, 709 electrochemistry, 713 electronic spectra, 712 ESR spectra, 712 IR spectra, 712 magnetic properties, 710 synthesis, 709 cyanides, 703 fluorophosphine, 716 isocyanides crystallography, 708 electrochemistry, 709 spectroscopy, 708 synthesis, 707 1,10-phenanthroline, 709 electrochemistry, 713 electronic spectra, 712 ESR spectra, 712 IR spectra, 712 magnetic properties, 710 synthesis, 709 tertiary phosphines dinitrogen, 713 tris(bipyridyl)... 

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