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[摘要]:The first catalytic enantioselective Friedel-Crafts alkylation of pyrrole with 2,2,2-trifluoroacetophenones to give pyrroles with a trifluoromethyl-substituted tertiary alc. moiety bearing a quaternary stereogenic center, e.g. I (R = Ph, 3-FC6H4, Et, etc.), is described. The reaction is achieved in the presence of a 3,3'-dibromo-BINOL-Zr(IV) complex to give the expected products with high yields (up to 98%) and good enantioselectivities (up to 93% ee). The abs. stereochem. of the products has been detd. by chem. correlation. |
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