Palladium-catalyzed reactions in the synthesis of 3- and 4-substituted indoles. 2. Total synthesis of the N-acetyl methyl ester of (.+-.)-clavicipitic acids
Palladium-catalyzed reactions in the synthesis of 3- and 4-substituted indoles. 2. Total synthesis of the N-acetyl methyl ester of (.+-.)-clavicipitic acids
Optically pure (R)-N-Boc- or (R)-Cbz-4-bromo-N-methyl-1-tosyltryptophan methyl ester (11a or b) was synthesized in 2 steps from (R)-N-acetyl-4-bromo-1-tosyltryptophan methyl ester (7) by simultaneous N-methylation and deacetylation using methyl trifluoromethanesulfonate (TfOMe) in the presence of 2,6-di-tert-butyl-4-methylpyridine (DTBMP).
Palladium-catalyzed reactions in the synthesis of 3- and 4-substituted indoles. 2. Total synthesis of the N-acetyl methyl ester of (.+-.)-clavicipitic acids
作者:Peter J. Harrington、Louis S. Hegedus、Keith F. McDaniel