Investigation of steric and electronic effects in the copper-catalysed asymmetric oxidation of sulfides
作者:Graham E. O'Mahony、Kevin S. Eccles、Robin E. Morrison、Alan Ford、Simon E. Lawrence、Anita R. Maguire
DOI:10.1016/j.tet.2013.08.063
日期:2013.11
in the copper-catalysed asymmetricoxidation of aryl benzyl, aryl alkyl and alkyl benzyl sulfides have been investigated. The presence of an aryl group directly attached to the sulfur is essential to afford sulfoxides with high enantioselectivities, with up to 97% ee for 2-naphthyl benzyl sulfoxide, the highest enantioselectivity achieved to date for copper-catalysed asymmetric sulfoxidation. In contrast
2,6-Dicarboxypyridinium chlorochromate (2,6-DCPCC) was found to be an efficient reagent for the conversion of thiols to disulfides and sulfides to sulfoxides under neutral and anhydrous conditions in good to excellent yields. Selective oxidation of thiols in the presence of sulfides at room temperature is also observed with this reagent.
Alkyl Sulfides as Promising Sulfur Sources: Metal-Free Synthesis of Aryl Alkyl Sulfides and Dialkyl Sulfides by Transalkylation of Simple Sulfides with Alkyl Halides
A site‐selective metal‐free dealkylative approach to synthesize aryl alkyl and symmetrical dialkyl sulfides has been developed. This procedure is convenient and has wide functional group tolerance giving rise to sulfides carrying various alkyl chains from simple alkyl sulfides and alkyl halides in good to excellent yields. This transalkylation proceeds by an ionic mechanism via sulfonium intermediates
DTBP-mediated controlled oxidative C–S bond cleavage/annulation cascade: construction of indenones
作者:Farnaz Jafarpour、Banafshe Rahimi
DOI:10.1039/d2nj06286k
日期:——
A novel controlled DTBP-mediated oxidative C–S bond cleavage/annulation cascade is devised. This approach enables the controlled formation of carbonyl intermediates frombenzyl thioethers to participate in annulation reactions with alkynes to offer privileged indenone skeletons.