Bis(benzotriazolyl)methanethione

Abstract

This feature focuses on a reagent chosen by a postgraduate, highlighting the uses and preparation of the reagent in current research Bis(benzotriazolyl)methanethioneCompiled by Archana Singh Archana Singh was born in Varanasi, Uttar Pradesh, India, in 1981. She obtained her B.Sc. from the P. G. College in 2003 and her M.Sc. in chemistry from the U. P. College, Varanasi, in 2005. She joined the research group of Dr. Vinod K. Tiwari at the Banaras Hindu University. Her current research is focused on the development of new synthetic methodologies and on carbohydrate synthesis for medicinal interests.

Mechanochemical Organic Synthesis: The Art of Making Chemistry Green

“…In an attempt to advance the mechanochemistry of thioureas, which has been extensively investigated in our group, 12 we turned our attention to thiocarbamoyl benzotriazoles. Specifically, we explored the solid-state reactivity of bis(benzotriazolyl)methanethione (9) 13 as an easy-to-handle and much less toxic substitute for thiophosgene in the synthesis of isothiocyanates. 14 Surprisingly, thione 9 reacts with alkyl and aryl amines in different ways in solution; whereas stoichiometric reaction between 9 and an alkyl amine yields the corresponding alkyl thiocarbamoyl benzotriazole as a stable compound, aromatic derivatives proved to be unstable and too reactive in solution, directly affording the corresponding aromatic isothiocyanates (Figures 2a and 2b).…”

“…14 Because these compounds readily decomposed in the solution environment, growing single crystals suitable for crystallographic analysis was not an option. For this reason, we resorted to structure determination directly from PXRD data obtained by high-intensity synchrotron radiation measurements, in combination with solid-state 13 C and 15 N NMR experiments. PXRD analyses of three derivatives indicated that the molecular structure indeed corresponded to those of thiocarbamoyl benzotriazoles.…”

“…The MASSPC approach was tested in a photocatalytic aerobic oxidation of diphenylacetylene (13) to give the 1,2diketone benzil (14) in the presence of 4-chlorothiophenol as an additive. Initially, we employed a blue or green LED strip as a source of visible light; this was wrapped around the glass milling jar, which oscillated at a frequency of 27 Hz (Figure 6b).…”

“…This setup was eventually replaced with a fixed LED reactor, because the strip connection to the power source broke at higher milling frequencies. (c) The model photocatalytic oxidation of diphenylacetylene(13) to benzil(14). (d) The effects of various photocatalysts (left) and various input powers/light intensities (right) on the yield of benzil.…”