Synthesis of 4-substituted 3-chloro-1,2,5-thiadiazoles from monosubstituted glyoximes

Recent Developments in the Synthesis of 1,2,5-Thiadiazoles and 2,1,3-Benzothiadiazoles

“…Monosubstituted glyoximes gave under the same conditions 4-substituted 3-chloro-1,2,5-thiadiazoles. 17 The proposed mechanism for the formation of 1,2,5thiadiazoles 1 and their 2-oxides 18 including the oxime…”

Copper(II)-Dioxygen Facilitated Activation of Nitromethane: Nitrogen Donors for the Synthesis of Substituted 2-Hydroxyimino-2-phenylacetonitriles and Phthalimides

“…Of these, 2-hydroxyimino-2phenylacetonitriles (2) are useful building blocks for the construction of polynitrogen organic substances, especially for the synthesis of peptides and/or nitrogen-containing heterocyclic compounds (Itoh et al, 1975;Kunai et al, 1990;Neel and Zhao, 2018;Alam et al, 2020). A few methods are available for the synthesis of these compounds, including the condensation of phenylketone/benzaldehyde and the cyanidation of their secondary products (Schemes 1A,B) (Ma et al, 1999;Uysal, 2010;Lemercier and Pierce, 2014;Kryshenko et al, 2016;Ushakov et al, 2019), the nitrosylation and nitridation of benzyl-cyanide (Schemes 1C,D) (Dubery et al, 1999;Bohle and Perepichka, 2009;Bohle et al, 2013;Neel and Zhao, 2018), and the nitration and nitrosation of styrene (Schemes 1E,F) (Kunai et al, 1990;Alam et al, 2020). However, these methods suffer from several drawbacks, such as the use of toxic reagents, rigorous reaction conditions, the cost of starting materials, multistep processes, and/or low yields.…”