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Addition of 1‐pyrrolidinocyclohexene to (E)‐(1‐methyl‐2‐oxoindolin‐3‐ylidene)acetophenone followed by acid hydrolysis was diastereoselectively controlled to give (±)‐7a (3R*,1′S*,2′S*) or (±)‐7b (3S*,1′R*,2′S*), the structures of which were supported by ¹H NMR spectroscopic data and corroborated by X‐ray diffraction analysis. The change in configuration at the C‐2′ centre greatly affected the geometries of the two diastereomers, both in solid and in solution. An explanation of the observed diastereoselectivity is provided. An approach to the N‐methylwelwitindolinone C skeleton from 7b as a starting material, by insertion of a rhodium carbenoid into the C(4)−H indole position, was abandoned because of the initial experimental results, which are also described. (© Wiley‐VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)