The remarkable effect of the 7-substituent in the diastereoselective oxidative rearrangement of indoles: asymmetric synthesis of 3,3-disubstituted oxindoles.

The nature of the 7-substituent has a remarkable effect on the diastereoselectivity of the oxidative rearrangement of indole-2-carboxamides derived from (S)-2-methoxymethylpyrrolidine into chiral 3,3-disubstituted oxindoles.