Direct CH Bond Activation of Benzoxazole and Benzothiazole with Aryl Bromides Catalyzed by Palladium(II)-N-heterocyclic Carbene Complexes
CHINESE JOURNAL OF CHEMISTRY, vol.36, no.9, pp.837-844, 2018 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 36 Issue: 9
- Publication Date: 2018
- Doi Number: 10.1002/cjoc.201800166
- Journal Name: CHINESE JOURNAL OF CHEMISTRY
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Page Numbers: pp.837-844
- Keywords: benzimidazolium bromide, benzoazoles, direct CH bond activation, N-heterocyclic carbene, palladium, DIRECT ARYLATION, H BOND, HETEROAROMATIC-COMPOUNDS, COUPLING REACTION, DERIVATIVES, CHLORIDES, SYSTEM, FUNCTIONALIZATION, (BENZO)OXAZOLES, HETEROARENES
- Inonu University Affiliated: Yes
Abstract
Herein, we report that a series of novel palladium(II)-NHC complexes (NHC=N-heterocyclic carbene) were synthesized. The structures of all novel complexes were characterized by H-1 NMR, C-13 NMR, FT-IR spectroscopy and elemental analysis techniques. These palladium(II)-NHC complexes were tested as efficient catalysts in the direct CH bond activation of benzoxazole and benzothiazole with aryl bromides in the presence of 1 mol% catalyst loading at 150 degrees C for 4 h. Under the given conditions, various aryl bromides were successfully applied as the arylating reagents to achieve the 2-arylbenzoxazoles and 2-arylbenzothiazoles in acceptable to high yields.