Base‐Promoted Three‐Component Cyclization and Coupling Strategy for the Synthesis of Substituted 3‐Aryl‐5‐thio‐1,3,4‐thiadiazole‐2‐thiones

Abstract

An effective base-promoted cyclization and coupling strategy for the construction of substituted 3-aryl-5thio-1,3,4-thiadiazole-2-thiones from phenylhydrazines, olefins and CS 2 is developed through employing CS 2 as a sulfur feedstock. The reaction proceeds under mild reaction conditions in the absence of any external catalysts, transition metals and ligands. The one-step three-component procedure also shows the merits of simple operation, using available starting materials, wide substrate scopes, and high atom and step economy. This reaction provides facile access to substituted 3-aryl-5-thio-1,3,4-thiadiazole-2-thiones, which could be used in the field of drug research.

Copper-Catalyzed Phosphorylation of N,N-Disubstituted Hydrazines: Synthesis of Multisubstituted Phosphorylhydrazides as Potential Anticancer Agents

“…As useful synthetic strategies, various new direct P­(O)–N bond formation methodologies are emerging through the P­(O)–N cross-coupling process, including photocatalyzed oxidation, electrochemical oxidation, transition-metal-catalyzed oxidation, I 2 -catalyzed oxidation, Tf 2 O-promoted activating strategy, diselenide-mediated catalysis, Atherton–Todd reaction, and so on. Organic hydrazines are a class of highly versatile and easily accessible coupling partners in organic synthesis . We also reported a photocatalyzed intermolecular coupling of N , N -disubstituted hydrazines with β-ketonitriles to hydrazonamides .…”

Direct intermolecular three-component aminotrifluoromethylation of styrenes by visible-light-photoredox catalysis

“…As a part of our ongoing investigation on green synthetic methods based on phenylhydrazines, 16 herein we demonstrated a visible-light-photoredox-catalyzed intermolecular three-component aminotrifluoromethylation for the synthesis of various aminotrifluoromethyl organic compounds from styrenes with phenylhydrazines and Togni's reagents/fluoroalkyl iodides (Scheme 1e). Here, the direct formation of C–N/C–C bonds showed the advantages of being operational simple, having good functional group tolerance, and operating in mild conditions.…”

Metal-Free Temperature-Controlled Intermolecular [3 + 2] Annulation to Access Benzo[d]thiazole-2(3H)-thiones and Benzo[d]thiazol-2(3H)-ones

“…21 Recently, our group successfully developed an effective cyclization of phenylhydrazines, olefins, and CS 2 to afford substituted 3-aryl-5-thio-1,3,4-thiazole-2-thiones through using CS 2 as a sulfur source. 22 In this context, we herein discovered a direct C−S/C−N bond formation strategy for constructing benzo[d]thiazole-2(3H)-thiones and benzo-[d]thiazol-2(3H)-ones from N,N-disubstituted arylhydrazines with CS 2 at different reaction temperatures, in which no prefunctionalization of the starting materials was needed (Scheme 1f). Moreover, the facile intermolecular [3 + 2] annulation reaction was carried out without the addition of any external catalysts, transition metals, bases, ligands, and oxidants with high step economy.…”

“…Organic hydrazines have been proved as valuable precursors for the preparation of diverse nitrogen-containing compounds . Recently, our group successfully developed an effective cyclization of phenylhydrazines, olefins, and CS 2 to afford substituted 3-aryl-5-thio-1,3,4-thiazole-2-thiones through using CS 2 as a sulfur source . In this context, we herein discovered a direct C–S/C–N bond formation strategy for constructing benzo­[ d ]­thiazole-2­(3 H )-thiones and benzo­[ d ]­thiazol-2­(3 H )-ones from N,N-disubstituted arylhydrazines with CS 2 at different reaction temperatures, in which no prefunctionalization of the starting materials was needed (Scheme f).…”