One‐Pot Synthesis of Triazolothiadiazepine 1,1‐Dioxide Derivatives via Copper‐Catalyzed Tandem [3+2] Cycloaddition/N‐Arylation

Abstract

A practical and efficient synthesis of tri-A C H T U N G T R E N N U N G azolothiadiazepine-1,1-dioxide derivatives via copper-catalyzed [3 + 2] cycloaddition, followed by N-arylation is described. The method is also applicable to the synthesis of indoline-and thiophenefused triazolothiadiazepine 1,1-dioxide derivatives.

Syntheses of indolo[1,2-a]quinazolinone derivatives via palladium catalyzed intramolecular C–H amidation

“…In our earlier experiments, we found that DMSO, copper iodide and potassium carbonate at 80 °C gave the best results for N -arylation. 8 a Hence, we investigated the reaction of 2-iodo- N -methylbenzamide and indole in the presence of copper iodide and potassium carbonate in DMSO at 80 °C. Under these conditions, the desired 2-(1 H -indol-1-yl)- N -substituted benzamide was produced in 85% yield.…”

“…A copper catalyzed C–N bond forming reaction is frequently used in the synthesis of various N-heterocycles. 7 In our recent research, we focused our attention on copper catalyzed C–C and C–N bond formation reactions of 2-iodobenzamide derivatives for use in the construction of various heterocycles, including 2-aminophenylbenzoxazoles, 8 a isocoumarin derivatives 8 b and fused sultam derivatives. 8 c In a continuation of this effort, we wish to report on the synthesis of indolo[1,2- a ]quinazolinone derivatives from 2-iodobenzamide derivatives.…”

“…7 In our recent research, we focused our attention on copper catalyzed C–C and C–N bond formation reactions of 2-iodobenzamide derivatives for use in the construction of various heterocycles, including 2-aminophenylbenzoxazoles, 8 a isocoumarin derivatives 8 b and fused sultam derivatives. 8 c In a continuation of this effort, we wish to report on the synthesis of indolo[1,2- a ]quinazolinone derivatives from 2-iodobenzamide derivatives. Our strategy for this synthesis involves the N -arylation of indole derivatives under Ullman conditions to give 2-indolylbenzamide derivatives followed by C–H amidation.…”

“…In addition, the reaction proceeded at comparatively lower temperature than the literature procedures. 8 a The reason for this efficient reaction in absence of a ligand can be attributed to the ortho effect caused by the N -phenylamide. 10 On the other hand, the Fu and Bao groups reported on the synthesis of azoquinazolinone derivatives by Cu( i )-catalyzed C–N bond coupling/C–H activation/C–N bond forming reactions in an atmosphere of O 2 .…”

One‐Pot Tandem Synthesis of 2‐Arylbenzoxazole Derivatives via Copper‐Catalyzed CN and CO Bond Formation

“…Hence, we focused our recent research on tandem one‐pot procedures for use in the synthesis of various heterocyclic compounds 4. We recently reported on a copper‐catalyzed one‐pot tandem process for the synthesis of sultam‐fused triazoles 5. In a continuation of this research, we discovered a paper by Fu and co‐workers regarding the reaction of 2‐halo‐ N ‐(2‐haloaryl)benzamide with ethylcyanoacetate or malononitrile to give benzimidazo[1,2‐ b ]isoquinolin‐11‐one derivatives 6.…”