Ceric ammonium nitrate (CAN) as a green and highly efficient promoter for the 1,4-addition of thiols and benzeneselenol to α,β-unsaturated ketones
作者:Cheng-Ming Chu、Shijay Gao、M.N.V. Sastry、Chun-Wei Kuo、Chaowei Lu、Ju-Tsung Liu、Ching-Fa Yao
DOI:10.1016/j.tet.2006.12.018
日期:2007.2
efficient process for the 1,4-addition of thiols and benzeneselenols to various α,β-unsaturatedketones using a catalytic amount of CAN with excellent product yields is described. This inexpensive, nontoxic, and readily available catalytic ceric(IV) ammonium nitrate system efficiently catalyzes conjugate addition reactions between thiol derivatives and various α,β-unsaturatedketones under solvent-free conditions
The iron(III) chloride-mediated 1,4-addition of mercaptans to α,β-unsaturated ketones and esters under solvent free conditions
作者:Cheng-Ming Chu、Wan-Ju Huang、Chaowei Lu、Pohsi Wu、Ju-Tsung Liu、Ching-Fa Yao
DOI:10.1016/j.tetlet.2006.07.151
日期:2006.10
The 1,4-addition of various thiols to alpha,beta-unsaturated ketones was completed rapidly in the presence of a catalytic amount (2-3 mol %) of anhydrous iron(III) chloride under solvent free conditions and an air atmosphere. Anhydrous iron(III) chloride is more active than that of other ferric salts. With more reactive and/or less steric reagents (1a-c and/or 2a-2c), expeditious conditions (short reaction times at room temperature) could be employed. With less reactive and/or steric reagents (1d-g and/or 2d-e), a slight increase in reaction time was required, but high yields were obtained. The FeCl3 catalyst causes preferential interactions with alpha,beta-unsaturated ketones present in the reaction. (c) 2006 Published by Elsevier Ltd.
Organic reaction in water. Part 2: Michael addition in water without phase transfer agents
作者:Flavia Martins da Silva、Adriana Kniaseff Gomes、Joel Jones, Jr.
DOI:10.1139/cjc-77-5-6-624
日期:——
The Michael additions of dicarbonyl compounds, nitroalkanes, and thiols to 2-cyclohexen-1-one can be accomplished in water without phase transfer agents. The reaction is extremely sensitive to the pH of the reaction media, and therefore, the methodology can be optimized with the control of this variable. The best pH depends on the used nucleophile.
Pronounced Catalytic Effect of a Micellar Solution of Sodium Dodecyl Sulfate (SDS) on the Efficient C-S Bond Formation<i>via</i>an Odorless Thia-Michael Addition Reaction through the<i>in situ</i>Generation of<i>S</i>-Alkylisothiouronium Salts
Abstractmagnified imageA pronounced catalytic effect of sodium dodecyl sulfate (SDS) was observed on thein situproduction ofS‐alkylisothiouronium saltsviathe reaction of primary, allyl and benzyl halides with thiourea in SDS droplets .Hydrolysis of the generatedS‐alkylisothiouronium salts in the palisade layer of the droplets produces the corresponding thiol moieties which are immediately added to the electron‐deficient olefins that are present in the micellar core to produce the thia‐Michael adducts. The entire route is an almost odorless process. The yields of the products are good to excellent and the method is applicable to large‐scale operation without any problem.
Mild Hydrosulfenylation of Olefins under Neutral Conditions Using a Defined NHC-Ligated Iron–Sulfur Catalyst
作者:Isabel Alt、Philipp Rohse、Bernd Plietker
DOI:10.1021/cs4009336
日期:2013.12.6
A defined NHC-Fe-S complex proved to be an efficient catalyst for the selective hydrosulfenylation of alpha/beta-unsaturated ketones or vinylnitriles. A wide range of different aliphatic thiols were transferred in this atom-economic reaction into the corresponding thioethers. Mild reaction conditions, equimolar amounts of substrates, low catalyst loadings, and mild reaction conditions are characteristic for this transformation.