3608-45-5Relevant academic research and scientific papers
Facile Protocols towards C2-Arylated Benzoxazoles using Fe(III)-Catalyzed C(sp 2 -H) Functionalization and Metal-Free Domino Approach
Vodnala, Nagaraju,Gujjarappa, Raghuram,Kabi, Arup K.,Kumar, Mohan,Beifuss, Uwe,Malakar, Chandi C.
supporting information, p. 1469 - 1478 (2018/05/25)
Considering their growing attention in the field of medicinal chemistry and drug-discovery research, the facile and convenient approaches towards the preparation of 2-aryl benzoxazole derivatives have been described. The transformation is accomplished by using Fe(III)-catalyzed C-H activation of benzoxazoles with boronic acids to obtain a wide range of C2-arylated benzoxazoles in high yields. The developed method excludes the formation of self-coupling compounds as side products. On the other hand, the synthesis of the products is also achieved via a metal-free domino protocol by the reaction between 1-nitroso-2-naphthol and acetophenones using catalytic amounts of CBr 4 in the presence of Cs 2 CO 3 as base. The devised tandem method avoids the use of pre-activated α-haloketones as substrates. Due to their immense impact in marketed drugs and molecules under clinical trial, the described method can be a powerful tool for their synthesis which restricts the use of precious metals as catalyst.
Cyclization of α-Oxo-oximes to 2-Substituted Benzoxazoles
Katritzky, Alan R.,Wang, Zuoquan,Hall, C. Dennis,Akhmedov, Novruz G.,Shestopalov, Aleksandr A.,Steel, Peter J.
, p. 9093 - 9099 (2007/10/03)
Reactions of oximes 9, 17, and 19 with electrophiles 15a-f and 24 in the presence of anhydrous potassium carbonate or triethylamine give 2-substituted condensed ring oxazoles 10, 16a-c, 18a-d, 20a-c, and 25 in a new general route to these compounds.
