Baylis-Hillman acetates in organic synthesis: convenient one-pot synthesis of α-carboline framework - a concise synthesis of neocryptolepine

A convenient, facile, and one-pot methodology for the synthesis of alpha-carbolines from Baylis-Hillman (BH) acetates, involving three steps (reactions), (1) mono alkylation of 2-nitroarylacetonitriles with BH-acetates, (2) reduction of nitro group into amino group using Fe/AcOH and (3) formation of two (five and six membered) rings, is presented. This methodology is successfully applied to the synthesis of bioactive alkaloid neocryptolepine.