10.1080/10426507.2016.1255621
The research focuses on the development of two methodologies for synthesizing sulfur heterocycles (S-heterocycles) and mixed nitrogen-sulfur heterocycles (N,S-heterocycles) through metal-mediated domino reactions. The first methodology involves a cyclocarbopalladation/cross-coupling domino process, utilizing propargyl sulfides or ynethioethers as starting materials and Pd(PPh3)4 as a catalyst, with Stille or Suzuki-Miyaura coupling partners like 2-furyl, 2-thienyl, allyl, and vinyl tributylstannanes, or arylboronic acids. This approach yields benzene-fused five- or six-membered sulfur heterocycles with a stereodefined tetrasubstituted exocyclic double bond. The second methodology is a three-component domino reaction between 2-aminophenyl disulfide, copper cyanide (CuCN), and an electrophile, which accesses N-substituted 2-amino benzothiazoles. The experiments also explore the synthesis of N-substituted 2-imino benzothiazoles using N-protected 2-aminoaryl disulfides as precursors. The analyses used to confirm the structures of the synthesized compounds include X-ray crystallography, with crystallographic data deposited at the Cambridge Crystallographic Data Center.