A microwave-assisted three-component protocol involving N-1 alkylation of 2-alkynylindoles with epichlorohydrin, ring opening of the epoxide with sodium azide, and an intramolecular Huisgen azide–internal alkyne 1,3-dipolar cycloaddition domino sequence has been described. The efficacy of the methodology has been demonstrated by treating various 2-alkynylindoles (aromatic/aliphatic) with epichlorohydrin and sodium azide furnishing annulated tetracyclic indolodiazepinotriazoles in satisfactory yields.
A PEG-mediated green synthesis of 6-pyrazinyl-/fused pyrazinylquinazolin- 4(3H)-ones was developed starting from 6-iodo-3-methyl-2-phenylquinazolin- 4(3H)-one by means of quinazolinone-based internal alkyne/1,2-diketone as intermediates using the Castro?Stephen coupling reaction/potassium permanganate mediated oxidation and cyclocondensation reactions.
Microwave-assisted three-component domino reaction: Synthesis of indolodiazepinotriazoles
