Sc. Shim et al., SYNTHESIS OF INDOLES FROM N-SUBSTITUTED ANILINES AND TRIETHANOLAMINE BY A HOMOGENEOUS RUTHENIUM CATALYST, Synthetic communications, 26(7), 1996, pp. 1349-1353
N-substituted anilines react with triethanolamine in the presence of a
catalytic amount of a homogeneous ruthenium catalyst to give the corr
esponding 1-substituted indoles in good yields.