Reissert-like Alkenylation of Azaaromatic Compounds with Alkenylzirconocene Chloride Complexes
摘要:
Reissert-like alkenylation of azaaromatic compounds by the use of alkenylzirconocene chloride as a nucleophile was carried out in the presence of a stoichiometric amount of ClCO2Et. The regioselectivity of the nucleophilic attack depends on reacting heterocycles, solvent, and the presence of copper catalyst. Thus, the reaction of quinoline derivatives with alkenylzirconocene chloride in MeNO2 proceeded in a preferential 1,2-addition manner to give N-ethoxycarbonyl-2-alkenyl-1,2-dihydroquinolines, and the reaction of pyridine in CH2Cl2 under Cu(I)-catalyzed conditions proceeded in a 1,4-addition manner to give N-ethoxycarbonyl-4-alkenyl-1,4-dihydropyridine. The alkenylation of 3,4-dihydroisoquinoline with alkenylzirconocene chloride was also carried out in an enantioselective manner under Cu(I)/chiral Box-catalyzed conditions to give alkenylated tetrahydroisoquinoline compound (75%ee).
Reissert-like alkenylation of azaaromatic compounds by the use of alkenylzirconocene chloride as a nucleophile was carried out in the presence of a stoichiometric amount of ClCO2Et. The regioselectivity of the nucleophilic attack depends on reacting heterocycles, solvent, and the presence of copper catalyst. Thus, the reaction of quinoline derivatives with alkenylzirconocene chloride in MeNO2 proceeded in a preferential 1,2-addition manner to give N-ethoxycarbonyl-2-alkenyl-1,2-dihydroquinolines, and the reaction of pyridine in CH2Cl2 under Cu(I)-catalyzed conditions proceeded in a 1,4-addition manner to give N-ethoxycarbonyl-4-alkenyl-1,4-dihydropyridine. The alkenylation of 3,4-dihydroisoquinoline with alkenylzirconocene chloride was also carried out in an enantioselective manner under Cu(I)/chiral Box-catalyzed conditions to give alkenylated tetrahydroisoquinoline compound (75%ee).