Studies On Dehydration Of Alcohols To Construct C-P Bonds And C-H Bonds

Alcohols exist abundantly in nature.Because of the flexible reactivity of hydroxyl group,alcohols are widely used in organic synthesis.The dehydration of alcohols is applicable to construct carbon-carbon bonds and carbon-heteroatom bonds with water as a by-product,making the transformation to be one of the most sustainable methods for synthesizing functional molecules.This work focus on the construction of C-P bond anf C-H bonds via hydration of alcohols,and the specific contents come as follows:1.We disclosed a new method for constructing C-P bonds via cross dehydrative coupling between alcohols and P(O)-H compounds.Mediated by stoichiometric base,a variety of aryl ethanols couplled with secondary phosphine oxides,forming the corresponding beta-aryl phosphine oxides in good to high yields.F,Cl,Br and heterocycles are well tolerated,facilitating further functionalization of the products.In addition to the aryl ethanols,ethanol and n-heptanol are also workable under the reaction conditions,despite with a low yield.Mechanistic studies showed that this reaction would proceed via a path involving dehydration of alcohols to produce alkenes and subsequent addition of P(O)-H compounds to the resulting alkens.2.A novel Cu-catalyzed disproportionation reaction of biarylmethanols was developed.After being stirred in DCE at 110 ? for 12 h,this reaction proceeded completely to produce the corresponding equivalent biaryl methanes and biaryl ketones in high yields.Further studies including the mechanistic elucidation are underway in our laboratory.