33399-48-3Relevant articles and documents
Beyond the cyanine limit: Peierls distortion and symmetry collapse in a polymethine dye
Tolbert, Laren M.,Zhao, Xiaodong
, p. 3253 - 3258 (1997)
Theory predicts that cyanine dyes and related linear systems undergo symmetry collapse and bond localization at long chain lengths. Beyond this 'cyanine limit', the properties of these systems do not extrapolate from their shorter counterparts. To test this prediction, dipyridocyanines have been synthesized and shown to undergo such symmetry collapse with chain lengths as short as 13.
Synthesis of Aryl Sulfides by Metal-Free Arylation of Thiols with Diaryliodonium Salts under Basic Conditions**
Kalek, Marcin,Rajkiewicz, Adam A.,Sarkar, Sudeep,Wojciechowska, Natalia
, (2022/02/07)
Metal-free arylation of thiols with diaryliodonium salts has been developed. The application of a strong organic base enables the C?S bond formation under mild and experimentally simple conditions. The method allows for the synthesis of aryl sulfides containing a broad range of aryl groups from an array of thiols, including aryl, heteroaryl, and alkyl ones. The mechanism of the reaction was studied by DFT calculations, demonstrating that it proceeds via the inner sphere pathway involving formation of an Ar2I(SR) intermediate, followed by reductive elimination.
Mono- And Dinuclear α-Diimine Nickel(II) and Palladium(II) Complexes in C-S Cross-Coupling
Talukder, Md Muktadir,Miller, Justin T.,Cue, John Michael O.,Udamulle, Chinthaka M.,Bhadran, Abhi,Biewer, Michael C.,Stefan, Mihaela C.
, p. 83 - 94 (2021/01/14)
The usefulness of transition metal catalytic systems in C-S cross-coupling reactions is significantly reduced by air and moisture sensitivity, as well as harsh reaction conditions. Herein, we report four highly air- and moisture-stable well-defined mononuclear and bridged dinuclear α-diimine Ni(II) and Pd(II) complexes for C-S cross-coupling. Various ligand frameworks, including acenaphthene- and iminopyridine-based ligands, were employed, and the resulting steric properties of the catalysts were evaluated and correlated with reaction outcomes. Under aerobic conditions and low temperatures, both Ni and Pd systems exhibited broader substrate scope and functional group tolerance than previously reported catalysts. Over 40 compounds were synthesized from thiols containing alkyl, benzyl, and heteroaryl groups. Also, pharmaceutically active heteroaryl moieties are incorporated from thiol and halide sources. Notably, the bridged dinuclear five-coordinate Ni complex has outperformed the remaining three mono four- or six-coordinate complexes by giving almost quantitative yields across a broad substrate scope.
