(608g) Copper-Catalyzed Aerobic Oxidative Cyclization Between 2-Aminobenzothiazole and Ketone: An Approach to Benzo[d]Imidazo[2,1-b]Thiazole

Copper-Catalyzed Aerobic Oxidative Cyclization between 2-Aminobenzothiazole and Ketone: An Approach to Benzo[d]imidazo[2,1-b]thiazole

Abstract: Sulfur-containing heterocyclic compounds are frequently
found in naturally occurring compounds and generally show various biological
activities. ^[1]Benzo[d]imidazo[2,1-b]thiazole
is an important chemical building block in synthetic organic and biological
chemistry.^[2] A
facile, efficient, and simple protocol for the synthesis of benzo[d]imidazo[2,1-b]thiazole
through copper-catalyzed aerobic oxidative cyclization between 2-aminobenzothiazole
and ketone has been developed. The reaction proceeds smoothly to furnish the
products in atom economy. A variety of fused benzoimidazothiazole derivatives
were synthesized with satisfactory yields.

References:

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Rev. 2004 , 104,2239-2258. (b) Dawson, P. E.;
Muir, T. W.; Lewis, C. I.; Kent, S. B. H. Science. 1994,
266, 776-779.

[2] Mishra, S.; Monir, K.; Mitra, S.; Hajra, A. Org.
Lett. 2014, 16, 6084- 6087