Phosphorus oxides and sulfides

Similar upfield shifts for C-3/5 are observed with an axial R = alkyl, aryl, O or S. An axial methyl at the P atom in the 1-oxide, however, is shielded compared with an equatorial one. 31P resonances of phosphorus oxides and sulfides are strongly deshielded. Some examples show the differences (5 values in p.p.m.) Me3P, -62 Me4P+ I-, 25 Me3P=0, 36 Me3P=S, 59 MesP, unknown. Other physical methods, such asP=0 or P=S stretching frequencies and dipole moments, are sometimes very useful in conformational and structural determinations. 

Phosphorus compounds exhibit an enormous variety of chemical and physical properties as a result of the wide range ia the oxidation states and coordination numbers for the phosphoms atom. The most commonly encountered phosphoms compounds are the oxide, haUde, sulfide, hydride, nitrogen, metal, and organic derivatives, all of which are of iadustrial importance. The hahde, hydride, and metal derivatives, and to a lesser extent the oxides and sulfides, are reactive iatermediates for forming phosphoms bonds with other elements. Phosphoms-containing compounds represented about 6—7% of the compound hstiugs ia Chemical Abstracts as of 1993 (1). 

Spectroscopic, and Theoretical Studies on MoleculEu- Phosphorus Oxides and Oxide Sulfides J. Clade, F. Frick, and M. Jansen... 

Aminolysis of the corresponding halides is the preferred method for the synthesis of dialkylamino derivatives of boron,1 silicon,2 germanium,3 phosphorus,4 arsenic,5 and sulfur.6 (Dialkylamino) chlorosilanes are prepared stepwise by the reaction of silicon tetrachloride with dialkylamines. This method may be utilized equally well for the conversion of alkyl- or aryl-substituted halides [e.g., (CH3) SiCl4. ] or of oxide and sulfide halides (e.g., POCl3 or PSC13) to the corresponding dialkylamino compounds. 

Spectroscopic, and Theoretical Studies on Molecular Phosphorus Oxides and Oxide Sulfides... 

Phosphine sulfides tend to be toxic. When burned, they give off dangerous phosphorus oxide and sulfur oxide fumes. 

Oxidation of phosphorus by oxygen, for example, may yield three distinct oxides (P4O, P4O10, and PjO ), whereas oxidations by sulfur may yield one or more of three possible sulfides (P4S, P4S7, and Preaction between phosphorus and oxygen or sulfur depend not only on the atomic ratios of the components used, but also on reaction conditions.) Certain of the more important binary halides, oxides, and sulfides of this group are described in later sections of this chapter, but the list is only partial. 

RECENT SYNTHETIC, STRUCTURAL, SPECTROSCOPIC, AND THEORETICAL STUDIES ON MOLECULAR PHOSPHORUS OXIDES AND OXIDE SULFIDES... 

With the exception of P4O10, efficiency values between 0.61 and 0.65 have been obtained. This indicates that, in spite of the differences among the crystal structures of the phosphorus oxides and oxide sulfides, their space-fillings are very similar. 

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