Copper-Catalyzed Asymmetric Hydroallylation Of Alkynes

In the past few decades,it is widely used that the traditional precious metals(Ir,Pd,Rh,Ru)to develop catalyzed allylation reactions of which process is that the transition metal reacts with the allylic electrophile at first,subsequently,soft reagent(Pka <25)nucleophilic substitution of allyl intermediates to achieve this process;Furthermore noble metals have to more costly and accompanied by seriously polluted.While cheap metals(such as Cu),it usually reacts with allyl electrophiles to form allyl metal intermediates,and then it usually transmetallates with hard nucleophiles(Pka>25,usually metal organic reagents),undergoes reduction to eliminate to form alkylate.Although the method of copper-catalyzed that is cheap metal catalyst had overcome the problems of high cost and environmental pollution,allylation has been relatively mature,which still need to use metered metal organic reagents in the reaction.Above all which disadvantages are the functional group has poor compatibility,complicated preparation steps,high sensitivity to water and air,and is not easy to store,and some metal reagents such as organotin reagents are more toxic.In addition,in the allylation reaction that has been achieved,the method of constructing a large sterically hindered quaternary carbon stereo center is very limited.Based on a series of shortcomings of metal-organic reagents and the lack of methods for constructing large sterically quaternary carbon centers,a cheap,readily available,and stable raw material(such as unsaturated hydrocarbons)was developed to replace preprepared metalorganic reagent.And it is a work that the new method that can be used to construct the quaternary carbon stereogenic is a challenging but meaningful work.In this paper,only a catalytic amount of copper-hydrogen catalyzed allylation reaction is added to alkyne to form an alkenyl copper intermediate,and the allylic electrophile efficiently realizes the allylation product can effectively solve the needs of the reaction The use of metered metal reagents and substrates is not suitable for a wide range of disadvantages;high regioselectivity and high enantioselectivity are used to construct chiral SN2 'quaternary carbon stereocenters and contain 1,4-diene.Therefore,we studied the coupling of copper hydrogen to alkyne generated on site as an alternative organometallic reagent and electrophile to synthesize a series of derivatives containing stereocenters carbon and 1,4-diene.