YTTERBIUM METAL PROMOTED ALLYLATION OF DISULFIDES WITH ALLYL BROMIDE
摘要:
In the presence of a catalytic amount of methyliodide, ytterbium metal can promote the reductive cleavage of the S-S bond in disufides I to give ytterbium thiolates 2 which then react with allyl bromide to form the corresponding allylic sulfides 3 in good yields under mild and neutral conditions.
Catalyst-Free Imidation of Allyl Sulfides with Chloramine-T and Subsequent [2,3]-Sigmatropic Rearrangement
作者:Yubo Jiang、Fanyang Mo、Di Qiu、Chunxiang Kuang、Yan Zhang、Jianbo Wang
DOI:10.1002/cjoc.201200604
日期:2012.9
A facile synthesis of various allyl sulfonamides based on imidation of allyl sulfides with chloramine‐T and subsequent [2,3]‐sigmatropicrearrangement has been achieved without metal catalysts. The reaction completes smoothly within 10 min, providing excellent yields in environment friendly solvent of alcohol. Functional groups such as bromine, hydroxyl, protected amido and aldehyde are tolerant under
Yb(<scp>iii</scp>)-catalysed <i>syn</i>-thioallylation of ynamides
作者:Manash Protim Gogoi、Rajeshwer Vanjari、B. Prabagar、Shengwen Yang、Shubham Dutta、Rajendra K. Mallick、Vincent Gandon、Akhila K. Sahoo
DOI:10.1039/d1cc02611a
日期:——
incorporating a sulfide moiety at the α-position and an allyl group at the β-position of the ynamide. The transformation is successful under ytterbium(III)-catalysis, providing access to highly substituted thioamino-skipped-dienes with broad substrate scope. Thus, tetrasubstituted olefins (with four different functionalgroups: amide, phenyl, thioaryl/alkyl, and allyl on the carbon centers) are made in a single
本文报道的是一种顺式结合在α位的烯丙基在炔酰胺的β位的硫化物部分和ynamides的-thioallylation。该转化在镱 ( III ) 催化下成功,提供了获得具有广泛底物范围的高度取代的硫氨基跳过二烯的途径。因此,四取代的烯烃(在碳中心上具有四个不同的官能团:酰胺、苯基、硫代芳基/烷基和烯丙基)是由易于获得的 ynamides 一步制成的,从而保持完整的原子经济性。该反应可扩展到由炔酰胺合成selenoamino二烯的顺式-selenoallylation。DFT 研究和控制实验提供了对反应机制的深入了解。
Difluoroacetaldehyde
<i>N</i>
‐Triftosylhydrazone (DFHZ‐Tfs) as a Bench‐Stable Crystalline Diazo Surrogate for Diazoacetaldehyde and Difluorodiazoethane
study, we developed a bench-stable difluoroacetaldehyde N-triftosylhydrazone (DFHZ-Tfs) as an operationally safe diazo surrogate that can release in situ two low-molecular-weight diazoalkanes, diazoacetaldehyde (CHOCHN2 ) or difluorodiazoethane (CF2 HCHN2 ), in a controlled fashion under specific conditions. DFHZ-Tfs has been successfully employed in the Fe-catalyzed cyclopropanation and Doyle-Kirmse
Rh(II)-Catalyzed [2,3]-Sigmatropic Rearrangement of Sulfur Ylides Derived from Cyclopropenes and Sulfides
作者:Hang Zhang、Bo Wang、Heng Yi、Yan Zhang、Jianbo Wang
DOI:10.1021/acs.orglett.5b01542
日期:2015.7.2
Rh2(OAc)4-catalyzed [2,3]-sigmatropicrearrangement of sulfurylides is reported. A series of cyclopropenes were successfully employed for [2,3]-sigmatropicrearrangement by a reaction with either allylic or propargylic sulfides. Under the optimized conditions, the reaction afforded the products in moderate to excellent yields. In these transformations, the vinyl metal carbenes generated in situ from the cyclopropenes
Catalytic Asymmetric [2,3]-Sigmatropic Rearrangement of Sulfur Ylides Generated from Copper(I) Carbenoids and Allyl Sulfides
作者:Xiaomei Zhang、Zhaohui Qu、Zhihua Ma、Weifeng Shi、Xianglin Jin、Jianbo Wang
DOI:10.1021/jo025687f
日期:2002.8.1
Catalytic asymmetric sulfur ylide [2,3]-sigmatropicrearrangement of carbenoids generated from aryldiazoacetates has been investigated with a number of chiral Rh(II) and Cu(I) catalysts, and moderately high enantioselectivity (52-78% ee) can be achieved with Cu(MeCN)(4)PF(6)/2,2'-isopropylidenebis[(4S)-4-tert-butyl-2-oxazoline].