Synthesis Of S(Se Or Te)-aryl Phosphonates And Phosphorus Hydrogenation Reaction Of Alkyne Sulfides (Selenides Or Tellurides) Were Catalyzed By Cesium Hydroxide

Cesium hydroxide is a supper inorganic alkali with good solubility and stability,which can dissolve well in dipolar aprotic solvent(THF, NMP, DMF, DMSO, DMAC).This reaction catalyzed by cesium hydroxide provides several advantages such asmilder conditions, handle easily, simple work-up procedure, environmentalfriendliness and so on.Organic phosphorus plays a very important role in the whole field of chemistry.S-aryl(Se-aryl or Te-aryl) phosphorothioates are useful intermediates in organicchemistry and biochemistry. There are many reports in the literature for theirpreparation. However, these methods use toxic and explosive reagents, harshreaction conditions, or use the transition metal catalysis, which don’t act inaccordance with the concept of green chemistry.Cesium hydroxide can react with weak acid substances to give a stronglynucleophilic anion. The P-H bond in dialkyl phosphites is a polar bond whichexhibits weak acid. Therefore, we assume that cesium hydroxide could catalyze thereaction of diaryldisulfides(diselenides or tellurides) with dialkyl phosphites.Meanwhile, we plan out the phosphorus hydrogenation reaction of sulfides(selenidesor tellurides), in order to get alkenyl phosphorus containing aryl substituted byheteroatomic. Specific concrete definites are as follows:(1) The reaction of dialkyl phosphites with diaryldiselenides (diselenides ortellurides) was studied on. We systematically studied on effects of solvent, reactiontime, different catalysts, catalyst amount and substrate containing various functionalgroups on the reaction. The experimental results show that: the reaction was carriedout in air atmosphere and at room temperature. DMSO as solvent was the best choice.The reaction time of daryldiselenides(diselenides or tellurides) and O,O-dialkylphosphonates was20h,15h and7h. Among alkali metal hydroxides, CsOH showedthe best catalytic effect. The catalyst amount of20mol%was the best choice. Theyields of S(Se or Te)-aryl phosphonates were above78%.9compounds ofO,O-dialkyl-S-aryl phosphates,15compounds of O,O-dialkyl-Se-aryl phosphatesand9compounds of O,O-dialkyl-Te-aryl phosphates were synthesized. The productswere characterized by31P NMR,1H NMR,13C NMR, and MS.(2) The reaction of diethyl phosphite with alkyne sulfides(selenides or tellurides) catalyzed by cesium hydroxide was studied. The reaction of O,O-diethylphosphonate with alkynyl selenides(tellurides) didn’t provide the expect additionalproduct, it occurred the cleavage of Se-Csp(Te-Csp) bond and gave thecorresponding terminal alkynes and Se-aryl(Te-aryl) phosphoroselenoates in excelentyields. We systematically studied on effects of solvent, reaction time, differentcatalysts, catalyst amount and substrate containing various functional groups on thereaction. The experimental results show that: the reaction was carried out in airatmosphere and at room temperature. DMF as solvent was the best choice. Thereaction time of alkyne telenides or alkyne tellurides with O,O-diethyl phosphonateswas6h and5h. Among alkali metal hydroxides, CsOH showed the best catalyticeffect. The catalyst amount of20mol%was the best choice. The yields of thereaction were above85%.6compounds of terminal alkynes were synthesized. Theproducts were characterized by1H NMR,13C NMR and MS. This unexpecteddiscovery of this study provides a simple and effective new way for the deprotectionof alkynyl selenides(tellurides).