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Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Synthesis of 1,2,4-triazol-5-ylidenes and their interaction with acetonitrile and chalcogens
Nikolai I Korotkikh1, Gennady F Rayenko, Oles P Shvaika
1The L. M. Litvinenko Institute of Physical Organic and Coal Chemistry, Ukrainian Academy of Sciences, 70. R, Luxemburg Donetsk, 83114, Ukraine. cowley@mail.utexas.edu
Abstract:
Two new, more convenient methods for the synthesis of 1,2,4-triazol-5-ylidenes are described. Four new 1,2,4-triazol-5-ylidenes have been prepared using these methods: 1-(1-adamantyl)-3,4-diphenyl-1,2,4-triazol-5-ylidene (2a), 1-(1-adamantyl)-3-phenyl-4-(p-bromophenyl)-1,2,4-triazol-5-ylidene (2b), 1-(1-adamantyl)-3-phenyl-4-(alpha-naphthyl)-1,2,4-triazol-5-ylidene (2c), and 1-(1-adamantyl)-3,4-di(p-bromophenyl)-1,2,4-triazol-5-ylidene (2d). The X-ray crystal structures of 2d and the precursor salt 1-(1-adamantyl)-3,4-di(p-bromophenyl)-1,2,4-triazolium bromide (1e) are described. Compound 2a reacts with CH(3)CN via C-H insertion to form 1-(1-adamantyl)-3,4-diphenyl-5-cyanomethyl-5H-1,2,4-triazoline (3), and 2a and 2d react with elemental sulfur and elemental selenium, respectively, to form the corresponding thione (4) and selenone (5).
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