One-Pot Synthesis of 4-Alkynyl-1-Aza-9,10-Anthraquinones from 2-Acylethynyl-3-Amino-1,4-Naphthoquinones

Cyclization of 2-(3-oxoalk-1-ynyl)-3-amino-1,4-naphthoquinones under the action of hydrogen bromide followed by Sonogashira cross-coupling of the thus formed 4-bromo substituted azaanthraquinone with terminal acetylenes represent the one-pot synthesis of 4-alk-1-ynyl-1-aza-9,10-anthraquinones.