Some aromatic 1-aryl(and 1-aralkyl)-β-carbolines were prepared from their tetrahydro analogues by dehydrogenation over palladium on charcoal either in a Parr bomb or in refluxing toluene. The bomb reaction appears to be a better procedure for the preparations of aromatic β-carbolines with bulky C-1 substituents such as the naphthyl group. 1-(1-Naphthyl)- and 1-(2-naphthyl)-tetrahydro-β-carbolines were obtained by the cyclization of the Schiff bases N-(l-naphthylmethylene)- and N-(2-naphthylmethylene)-tryptamines, respectively. Other tetrahydro-β-carbolines with smaller C-1 substituents were prepared by the condensation of tryptamine with the appropriate aldehydes.