| As a natural inhibitory neurotransmitter widely existed in animals and plants,?-aminobutyric acid?GABA?have showed extremely important physiological functions.Moreover,substituted GABA skeleton,especially containing aromatic substituents at the?position,has been often observed in natural and synthetic biologically active molecules products and pharmaceuticals.And it can act as a ligand,catalyst,chiral additive.it is imperative for organic chemists to develop new synthetic procedures for obtaining these sub-units.D–A cyclopropanes,as particularly useful synthetic building blocks widely applied in various organic transformations,have received remarkable attention from chemists for a long time.O,S,C,N.,etc.atoms have been successfully used for nucleophilic ring opening of D-A cyclopropanes.Among these,successful Friedel–Crafts alkylation of D–A cyclopropanes with indole,N,N-dimethylaniline,and phenolic compounds were also reported to construct the?-aryl butyric acid skeletons.However,catalyzed asymmetric examples are rare,Therefore,we hope to create a way to achieve the asymmetric arylation of D-A aminocyclopropane.we developed the first enantioselective Friedel–Crafts alkylation reactions of?-naphthols with aminocyclopropane.A series of?-naphthyl?-amino acid derivatives,which had excellent enantioselectivity in the presence of Cu?OTf?2/BOX,were obtained with high yields.The kinetic resolution was found to dominatetheFriedel–Craftsalkylationreactions.Withthissystem,2-amino cyclopropane-1,1-dicarboxylates was obtained with high kinetic resolution.we firstly report the enantioselective ring-opening/Friedel–Crafts alkylation reactions of amino-cyclopropanes with 2-naphthols via kinetic resolution,for the preparation of the?-naphtha-1-yl GABA derivatives in good yields with excellent enantioselectivity and chemoselectivity.The utilization of this Friedel–Crafts alkylation reaction was further showcased by the synthesis of 1,3-oxazine derivatives. |
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