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Tris(pentafluorophenyl)borane-Catalyzed Carbenium Ion Generation and Autocatalytic Pyrazole Synthesis-A Computational and Experimental Study.

ABSTRACT: In recent years, metal-free organic synthesis using triarylboranes as catalysts has become a prevalent research area. Herein we report a comprehensive computational and experimental study for the highly selective synthesis of N-substituted pyrazoles through the generation of carbenium species from the reaction between aryl esters and vinyl diazoacetates in the presence of catalytic tris(pentafluorophenyl)borane [B(C₆ F₅ )₃ ]. DFT studies were undertaken to illuminate the reaction mechanism revealing that the in situ generation of a carbenium species acts as an autocatalyst to prompt the regiospecific formation of N-substituted pyrazoles in good to excellent yields (up to 81 %).

SUBMITTER: Dasgupta A

PROVIDER: S-EPMC8596400 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Tris(pentafluorophenyl)borane-Catalyzed Carbenium Ion Generation and Autocatalytic Pyrazole Synthesis-A Computational and Experimental Study.

Dasgupta Ayan A Babaahmadi Rasool R Pahar Sanjukta S Stefkova Katarina K Gierlichs Lukas L Yates Brian F BF Ariafard Alireza A Melen Rebecca L RL

Angewandte Chemie (International ed. in English) 20211012 46

In recent years, metal-free organic synthesis using triarylboranes as catalysts has become a prevalent research area. Herein we report a comprehensive computational and experimental study for the highly selective synthesis of N-substituted pyrazoles through the generation of carbenium species from the reaction between aryl esters and vinyl diazoacetates in the presence of catalytic tris(pentafluorophenyl)borane [B(C6 F5 )3 ]. DFT studies were undertaken to illumi ...[more]

PMID: 34590773

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