Facile synthesis of (polyfluoro)alkanesulfinyl 4-isoxazolines: a stepwise solvent- and catalyst-free approach or a one-pot process in water

Abstract

4-Isoxazolines are important motifs in various biologically interesting molecules and versatile synthons for the preparation of various cyclic and acyclic compounds. Herein, two green and facile protocols were reported for...

Solvent- and Catalyst-Free Synthesis of gem-Difluorinated and Polyfluoroarylated Compounds with Nucleophilic or Electrophilic Fluorine-Containing Reaction Partners, Respectively

“…Furthermore, when reactions are conducted under solvent-free conditions, solvation phenomena will not need to be considered, which may provide an opportunity for chemists to realize the reactions that could not be achieved in conventional solvents before. Therefore, developing novel reactions without requiring the usage of solvents and catalysts is an important subject in green chemistry [4][5][6].…”

N-Benzylhydroxylamine as a novel synthetic block in “C1N1” embedding reaction via α-C(sp3)–H activation strategy

“…These conversions typically involved a 1,3-dipolar cycloaddition process to yield isoxazolidine, isoxazoline and tetrahydro-1,2-oxazine derivatives (Scheme 1A-c). 6–8 Overall, owing to the high reactivity of the nitrogen and oxygen atoms of N -benzylhydroxylamine, these two sites are readily involved in the conversion of organic reactions. However, the direct use of N -benzylhydroxylamine as a “C1N1 synthon” in cyclization has not been reported before and remains an interesting and challenging goal.…”

Organocatalytic Asymmetric Construction of Spirooxazines via Chemoselective Cascade Addition of N-Substituted Hydroxylamine with Keto-bis-enone

“…Oxazines are a compelling class of heterocycles due to their extensive biological activities. 7 While they form a stereogenic center with another oxacycle in a spiro fashion, they create a complex three-dimensional architecture with higher Fsp, 3 which elevates their potential toward drug discovery and medicinal chemistry. 8 Interestingly, various biologically active molecules and natural products also contain spirooxazines as a core (Scheme 1B).…”

“…T he breakthrough discovery of Lovering et al revealed that molecules with a higher fraction of sp 3 carbon and chiral centers have a greater chance of translation to medicinal chemistry. 1 Subsequently, tremendous effort has been paid to synthesize enantioenriched spirocycles 2 and their biological applications 3 via versatile metal-catalyzed, 4 organocatalyzed, 5 and photocatalyzed reactions. 6 In this regard, there is always a demand for a new efficacious spiro-heterocyclic motif.…”