Facile synthesis of 2-perfluoroalkylated benzoxazolines and benzothiazolines

Synthesis of Organofluoro Compounds Using Methyl Perfluoroalk-2-ynoates as Building Blocks

“…Treatment of 2-aminophenols 24a or 2-aminothiophenols 24b with methyl perfluoroalk-2-ynoates 1 in refluxing MeOH (Scheme 8) successfully gave cyclic 25a or 25b successfully. [20] Both electron-donating and electron- withdrawing groups attached to the corresponding 24a or 24b were all suitable for this protocol. Compounds with various substituents, such as Me, t Bu, F, Cl, Br, NO 2 , and CO 2 H, all provided the corresponding products with 45-94% yields.…”

“…We then endeavored to explore the application of methyl perfluoroalk‐2‐ynoates 1 for the catalyst‐free synthesis of 2‐perfluoroalkylated benzoxazolines 25a and benzothiazolines 25b . Treatment of 2‐aminophenols 24a or 2‐aminothiophenols 24b with methyl perfluoroalk‐2‐ynoates 1 in refluxing MeOH (Scheme ) successfully gave cyclic 25a or 25b successfully 20. Both electron‐donating and electron‐withdrawing groups attached to the corresponding 24a or 24b were all suitable for this protocol.…”

Construction of N-Ferrocene Substituted Benzodihydrooxazoles via a Catalyst-Free Aza-Michael Addition/C(sp3)-O Bond Formation Tandem Reaction

“…Tandem reactions, in which multiple transformations are combined in a single procedural step, have been widely employed for the construction of complex molecules Benzodihydrooxazoles are an important class of nitrogen and oxygen-containing heterocycles which are prevalent in natural products, bioactive molecules and many other functional molecules [20][21][22][23][24][25]. Considerable efforts have been devoted to the synthesis of this unique skeleton, strategies such as cyclization of 2-aminophenol, transition-metal-catalyzed intramolecular C-H amination reactions and coupling reactions of benzoxazoles have been discussed [22,[26][27][28][29][30][31][32][33][34][35][36]. However, the drawbacks of these methods are the requirement of strong acids or bases, participation of transition metal catalysts, lengthy steps and high reaction temperatures.…”

Green Synthesis, Antimicrobial Activity and Cytotoxicity of Novel Fused Pyrimidine Derivatives Possessing a Trifluoromethyl Moiety

“…One drawback of introducing fluorine substituents into drug products is that it poses increased challenges in the manufacturing process. Therefore, fluorine‐containing building blocks can be considered to be a cornerstone in the field of fluoro‐organic compounds synthesis …”