Synthesis Of Mixed Phosphorotrithioates From White Phosphorus

Phosphorus and sulfur are important elements in life activities.They can form important substances such as protein,carbohydrate and hormone,which are very important to maintain life activities.In addition,phosphorothioates play an important role in agriculture,medicine,materials,synthesis and other fields.Therefore,the research on phosphorothioates compounds is also very meaningful and valuable.The traditional methods to synthesis phosphorothioates are mainly based on the organic phosphorus compounds,which are mainly prepared by PCl3.In industry,the intermediate of PCl3 is obtained by the reaction of white phosphorus with chlorine gas,and then the organic phosphorus compounds are obtained by reaction with corresponding organic reagents.This process also produces a large amount of HCl,which is not only unfriendly to the environment,but also corrodes the instrument.Therefore,we hope to synthesize organophosphorus compounds from white phosphorus without going through the PCl3 process.This paper mainly includes the following parts:Part 1:We have successfully developed the first general and high yielding synthesis of(R1S)2P(O)SR2 involving P4,disulfides and alkyl halides.The use of KOH as a base,DMSO-toluene as a solvent,makes this transformation practical and green.The operationally simple reaction shows a broad scope of substrates and a good functional group tolerance.This method opens the shortest and environmentally benign way to these mixed phosphorotrithioates of practical importance.The reaction is characterized by a complete conversion of white phosphorus.Moreover,this method can be easily adapted to large-scale preparation.Our mechanistic data suggest that the nucleophilic attack of potassium mercaptan(RSK)on S,S,S-trialkyl phosphorotrithioates and subsequent C-S bond cleavage,the Michaelis-Arbuzov-like dealkylation,are the key steps in the formation of(R1S)2P(S)OK.Part 2:Developed a one-pot method for the efficient synthesis of S-aryl-S,S-dialkyl trithiophosphate.S-(2-cyanoethyl)-S,S-dialkyl trithiophosphate and diaryliodonium salt are used as raw materials,DBU as a base and Cu(acac)2 is used as catalyst.The traditional method for constructing this target product is prepared by reacting environmentally sensitive phosphoryl chloride with mercaptans and thiophenols,which has poor reaction selectivity and is not easy to control.The raw material of this method can be directly prepared from white phosphorus,the operation is simple and the yield of the target product is high.Most importantly,this method developed a new reagent of thiophosphate for the synthesis of mixed trithiophosphate.