Synthesis of Luminescent Indolo[2,1- b]quinazolin-6(12 H)-ones via a Sequential Ugi/Iodine-Promoted Cyclization/Staudinger/Aza-Wittig Reaction

Mao-Lin Yang; Long Zhao; Hao-Ran Chen; Ming-Wu Ding

doi:10.1021/acs.joc.3c01955

Synthesis of Luminescent Indolo[2,1- b]quinazolin-6(12 H)-ones via a Sequential Ugi/Iodine-Promoted Cyclization/Staudinger/Aza-Wittig Reaction

J Org Chem. 2023 Dec 1;88(23):16424-16434. doi: 10.1021/acs.joc.3c01955. Epub 2023 Nov 9.

Authors

Mao-Lin Yang¹, Long Zhao¹, Hao-Ran Chen¹, Ming-Wu Ding¹

Affiliation

¹ National Key Laboratory of Green Pesticide, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, Central China Normal University, Wuhan 430079, P. R. China.

PMID: 37943255
DOI: 10.1021/acs.joc.3c01955

Abstract

A new efficient synthesis of indolo[2,1-b]quinazolin-6(12H)-ones via a sequential Ugi/iodine-promoted cyclization/Staudinger/aza-Wittig reaction was developed. The acid catalyzed three-component reactions of 2-azidobenzaldehydes, 2-[2-(trimethylsilyl)ethynyl]benzenamines (or o-aminoacetophenones), and isocyanides gave Ugi-3CR intermediates, which reacted subsequently with I₂/DMSO and triphenylphosphine to produce indolo[2,1-b]quinazolin-6(12H)-ones in good overall yields. The obtained indolo[2,1-b]quinazolin-6(12H)-ones were all colored in bright red or orange. Their luminescent property was studied preliminarily and some of them showed high molar absorption coefficients, strong fluorescence emission intensity, and good absolute light quantum yields.