Synthesis of indoles from pyridinium salts. 7. Sterically hindered alkyl-3-nitropyridinium salts in the synthesis of indoles

The introduction of bulky alkyl substituents (iso-Pr,tert-Bu) into any positions of the starting 3-nitropyridinium salt only increases the reaction time and decreases the yields of the corresponding alkylindoles somewhat.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 805–810, June, 1989.