Various syntheticapplications of 3-(cyanoacetyl)indoles, as well as syntheses of some related indoles, have been investigated. Diethyl 2-(1H-indol-3-yl)-2-oxoethylphosphonate and a methyl derivative thereof have been prepared in one step from indole. Moreover, it was demonstrated that 3-(cyanoacetyl)indoles are useful starting materials for the preparation of for example 3-(1H-indol-3-yl)-3-oxopropanamides