Reactions of Selenurane [10-Se-4 (C4)] with Alcohols, Thiols and Selenol. A Quest for Formation of a New a-Selenurane [10-Se-4 (C3O)], [10-Se-4 (C3S)] or [10-Se-4 (C3Se)]
作者:Soichi Sato、Naomichi Furukawa
DOI:10.1246/cl.1994.889
日期:1994.5
Bis(2,2′-biphenylylene)selenurane readily reacts with various alcohols, phenols, thiols and selenol to give ligand coupling or ipso-substitution products under mild conditions via a two-step mechanism involving a σ-selenurane [10-Se-4 (C3O)], [10-Se-4 (C3S)] and [10-Se-4 (C3Se)] or corresponding selenonium salts as intermediates.
A general method for the synthesis of five‐membered and six‐membered selenaheterocycles through Ag‐catalyzed C−Se bond‐forming reaction is reported. This reaction proceeds via intramolecular cyclization of arylboronic acids with selenium powder. Preliminary mechanism studies demonstrate that this transformation involves a selenium‐centred radical intermediate.
Mo‐Based Oxidizers as Powerful Tools for the Synthesis of Thia‐ and Selenaheterocycles
作者:Peter Franzmann、Sebastian B. Beil、Dieter Schollmeyer、Siegfried R. Waldvogel
DOI:10.1002/chem.201805938
日期:2019.2.6
A highly efficient synthetic protocol for the synthesis of thia‐ and selenaheterocycles has been developed. By employing a MoCl5‐mediated intramolecular dehydrogenative coupling reaction, a broad variety of structural motifs was isolated in yields up to 94 %. The electrophilic key transformation is tolerated by several labile moieties like halides and tertiary alkyl groups. Due to the use of disulfide
An application for dechalcogenization of aryl dichalcogenides via copper catalysis to synthesize aryl chalcogenides is disclosed. This approach is highlighted by the practical conditions, broad substrate scope, and good functional group tolerance with several sensitive groups such as aldehyde, ketone, ester, amide, cyanide, alkene, nitro, and methylsulfonyl. Furthermore, the robustness of this methodology