Catalysis, thiophosphate

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. 

The mechanism of an actual hydrolysis reaction catalyzed by this prototype phosphomonoesterase has never been studied stereochemically. This apparent omission is presumably explained by the very low catalytic efficiency of the enzyme toward phosphorothioate monoesters as compared to phosphate monoesters (75) certainly, chiral [ O, 0]phosphorothioate 0-ester substrates already exist, and methodology is available for the configurational analysis of the chiral [ 0, 0, 0]thiophosphate that would be produced if the chiral substrate were hydrolyzed in H2. In fact, the low catalytic reactivity of phosphorothioate O-esters and the high reactivity of phosphorothioate S-esters has been explained by the enzyme utilizing nucleophilic catalysis (an associate mechanism) to achieve hydrolysis of the phosphate ester bond 40). 

Ranu BC, Dey SS (2004) Catalysis by ionic liquid a simple, green and efficient proeedure for the Michael addition of thiols and thiophosphate to conjugated alkenes in ionie liquid, [pmlmjBr. Tetrahedron 60 4183 188... 

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