The present application describes a process for preparing compounds of the indole type of the formula in which A is a hydrocarbon radical which, together with the carbons to which it is attached, forms a substituted or unsubstituted mono- or polycyclic aromatic system which may contain one or more heteroatoms from the group consisting of N, O and S, and R1, R2 independently of one another are H, a saturated, linear or branched aliphatic C1-C20-hydrocarbon radical, an unsaturated, linear or branched aliphatic C2-C20-hydrocarbon radical, a saturated or unsaturated, unsubstituted or alkyl-substituted cycloaliphatic C3-C20-hydrocarbon radical or an aromatic C5-C20-hydrocarbon radical, where these radicals may contain in their molecular skeleton one or more heteroatoms from the group consisting of the halogens, N, P, O, S, Si, Sn and B and may be substituted or unsubstituted, by cyclization of alkynylaminoaromatics of the formula in which R1 and R2 are as defined in formula (I) and R1, R2 or A may be attached to an organic or inorganic carrier, which comprises carrying out the reaction in a polar aprotic ion-solvating solvent in the presence of a suitable compound of Na, K, Rb or Cs. Using this process, it is possible to prepare substituted indoles in a simple manner and in high yields.