The thermal reaction between nitrosoarenes and alkynes under alkylating conditions produces Nalkoxyindoles as the major products in moderate to good yields and excellent regioselectivity. Various electrophiles are used affording different N-O-protected hydroxyindoles in a multi-component fashion. Privileged acetylenic subtrates used in reactions with substituted nitrosoarenes are arylalkynes or propiolates. Potentially bioactive compounds and other classes of highly functionalizable indole products were prepared. Reactions between o-carbomethoxy-nitrosoarenes and arylacetylenes provided tricyclic compounds containing an acylaziridine indoline skeleton.