Thiophosphate/selenophosphate

The chemistry and the structures in this report have been organized by the main-group/chalcogen building block units (Fig. 14.1). At the start of 2000, we were beginning to understand aspects of the chemistry of chalcophosphates both as selenophosphates and thiophosphates. The thesis of Dr. Carl Evenson [14] and his subsequent papers discuss the composition phase diagrams of Y,... 

A similar reaction of methyl P-D-ribopyranoside (5) with P(NMe2)3 in dioxane gave 2,3,4-bicyclophosphite of P-methyl-D-ribopyranoside, 6a in 90% yield. It was sulfurated and selenated to give the corresponding thiophosphate 6b and selenophosphate 6c in 89 and 81% yields, respectively. Oxidation of 6a with hydrogen peroxide gave cyclic phosphate 6d (92%), whereas its hydrolysis in aqueous... 

The author hopes that this chapter has convinced the readers of the value of homogeneous catalysis for the synthesis of organophosphorus compounds and for organo-heteroatom compounds in a broader sense. Hydrosilylation and hydroboration are indispensable modern synthetic reactions in this category. The H-P addition reactions herein described joins them as a third member. Although this chapter does not cover, the addition reactions of the S-P and Se-P bonds in thiophosphates [39] and selenophosphates [40] to alkynes also proceed in the presence of transition metal catalysts. In view of the wide use of phosphorus compounds, the new procedures will find practical applications. 

Oxygen, sulfur, and selenium will add to the phosphorus atom to give compounds known as trialkyl phosphates, trialkyl thiophosphates, or trialkyl selenophosphates, respectively, as illustrated by the following equations ... 

A convenient, general and stereoselective synthesis of trisubstituted and tetra-substituted alkenes (144), which may contain a cyanide function, as well as trisubstituted episulphides (145) have been elaborated. The method makes use of readily available thiophosphates and selenophosphates (146) (Scheme 43). ... 

The same oxidation procedures apply to the conversion of trialkyl or triaryl thiophosphates and selenophosphates into phosphates [1007, 1194] (equation 541). 

In the oxide literature, there are several reviews specific to the different families, such as layered transition metal oxides and metal phosphonates. Synthesis of metal nitrides has been discussed by Di Salvo. Precursor synthesis of oxides, chalcogenides and other materials is being pursued with vigour. - Thus, single-molecule precursors of chalcogenide containing compound semiconductors have b n developed. Kanatzidis has reviewed the application of molten poly-chalcophosphate fluxes for the synthesis of complex metal thiophosphates and selenophosphates. 

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