Copper Hydride Catalyzed Regioselctive Reduction Of Allylic Phosphoric Esters

Regioselective reduction of allylic alcohol derivatives have been attracted much attention because of its applications in synthetic organic chemistry.Three main types of methods have been utilized for this transformation:metal hydride reduction of allylic alcohols or their derivertives,transition metal mediated or catalyzed regioselctive reduction,and a method involving the transformation of allylic alcohol to allylic diazene intermediate.Palladium catalyzed approach is much attractive because of the mild reaction condition and good functional group compatibility.However,allylic palladium chemistry makes the regioselectivity of the reduction depend on the structures of the substrates.Cyclopropane and cyclobutane are important subunit in naturally occurring coumpounds and bioactive compounds.They are also versatile synthetic intermediates.There are three main methods used to synthesize cyclopropanes from olefins:the halomethylmetal-mediated cyclopropanation reactions,the transition metal-catalyzed decomposition of diazocompounds,and the nucleophilic addition-ringclosure sequence.However,only part substituted allylic esters and homoallylic esters are applied.Cu(?)can catalyze highly regio-and stereoselective reduction of propargylic carbonates with hydrosilanes.Cu(?)catalysis is a new approach to gain cyclopropane and cyclobutane derivertives.In this thesis,we report copper catalyzed reductive 1,3-transposition of allylicphosphoric esters that proceeds with excellent regio-and stereochemical control.And copper hydride catalysis to olefins with ?-aromatic group can be utilized to prepare cyclopropanes.Chlorophosphates are important compounds for the synthesis of organophosphorus compounds by the phosphorylation of alcohols and amines.They are the substrates for synthesesin this thesis.However,conventional reported procedures have several disadvantages:the use of toxic reagents,metal-containing waste,undesired byproducts that are difficult to remove from the sensitive products,expensive or not commercially available starting materials,the use of large quantities of solvents,etc.A more convenient,efficient,and environment-friendly method is still desired.N-chlorosuccinimide is a widely available and efficient chlorinating reagent to afford chlorophosphates from dialkyl phosphites.Traditionally,the reactions are carried out in various organic solvents,and the purification of product produces a lot of waste organic solvents.We found that the reaction does not clearly depend on the type of solvent used in our experiments,which prompted us tooptimize the reaction process.The optimized process generates less or no waste solvent.