L. Jeannin et al., PRACTICAL SYNTHESES OF FUNCTIONALIZED OXO-1,2,3,4-TETRAHYDRO-BETA-CARBOLINE-3-CARBOXYLIC ACID-ESTERS, Synthetic communications, 26(9), 1996, pp. 1711-1719
Three methods have been proposed for the preparation of functionalized
o-1,2,3,4-tetrahydro-beta-carboline-3-carboxylates (3) from which the
''acylazide formation-Curtius rearrangement-acid catalyzed ring closu
re'' sequence starting from hemi-ester hemi-acids (8) seemed to be qui
te general.