title: In Situ generation of difluoromethyl diazomethane for [3+2] cycloadditions with alkynes.
abstract: A novel approach to agrochemically important difluoromethyl-substituted pyrazoles has been developed based on the elusive reagent CF2 HCHN2 , which was synthesized (generated in situ) for the first time and employed in [3+2] cycloaddition reactions with alkynes. The reaction is extremely practical as it is a one-pot process, does not require a catalyst or the isolation of the potentially toxic and explosive gaseous intermediate, and proceeds in a common solvent, namely chloroform, in air. The reaction is also scalable and allows for the preparation of the target pyrazoles on gram scale.
authors: Enamine Ltd. Matrosova 23, 01103 Kyiv (Ukraine) http://www.enamine.net. Pavel.Mykhailiuk@gmail.com, Pavel.Mykhailiuk@mail.enamine.net.|Taras Shevchenko National University of Kyiv, Chemistry Department, Volodymyrska 64, 01601 Kyiv (Ukraine). Pavel.Mykhailiuk@gmail.com, Pavel.Mykhailiuk@mail.enamine.net.
authors: Pavel K
authors: PK
authors: Mykhailiuk
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D018360:Crystallography, X-Ray; D061565:Cycloaddition Reaction; D003978:Diazomethane / Q000737:chemistry*; D005659:Fungicides, Industrial / Q000138:chemical synthesis / Q000737:chemistry; D008968:Molecular Conformation; D011720:Pyrazoles / Q000737:chemistry
chemical_list: D000480:Alkynes; D005659:Fungicides, Industrial; D011720:Pyrazoles; D003978:Diazomethane
keywords: alkynes; cycloaddition; difluoromethylation; fluorine; pyrazoles