Copper-catalyzed asymmetric sulfoxidation of aryl benzyl and aryl alkyl sulfides, using aqueous hydrogen peroxide as the oxidant, has been investigated. A relationship between the steric effects of the sulfide substituents and the enantioselectivity of the oxidation has been observed, with up to 93% ee for 2-naphthylmethyl phenyl sulfoxide, in modest yield in this instance (up to 30%). The influence
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
The first catalytic α-alkylation reaction of benzyl sulfides and 1,3-dithianes with styrenes and conjugated dienes was developed under mild conditions by using a readily available Brønsted base potassium bis(trimethylsilyl)amide (KHMDS) as catalyst. The reaction displayed good functional group tolerance, high efficiency, and excellent chemoselectivity. A series of desired alkylation products were obtained
Photochemical Functionalization of Heterocycles with EBX Reagents: C−H Alkynylation versus Deconstructive Ring Cleavage**
作者:Errika Voutyritsa、Marion Garreau、Maroula G. Kokotou、Ierasia Triandafillidi、Jérôme Waser、Christoforos G. Kokotos
DOI:10.1002/chem.202002868
日期:2020.11.11
The development of novel methodologies for the functionalization of saturated heterocycles is highly desirable. Herein, we report a cheap and efficient photochemical method for the C−H functionalization of saturated O‐heterocycles, as well as the deconstructive ring‐cleavage of S‐heterocycles, employing hypervalent iodine alkynylation reagents (ethynylbenziodoxolones, EBX). This photochemical alkynylation
A Facile One-Pot Synthesis of Alkyl Aryl Sulfides from Aryl Bromides
作者:Jungyeob Ham、Inho Yang、Heonjoong Kang
DOI:10.1021/jo049758h
日期:2004.4.1
one-pot synthetic method for the formation of alkylaryl sulfides from various alkyl halides and lithium aryl thiolates that are prepared in situ by direct halogen−lithium exchange is reported. In particular, the method overcomes many of the problems encountered in previous reports; it is very quick, catalyst-free, and does not involve use of unstable aryl thiols.