Silicon-based thiourea-mediated and microwave-assisted thio-Michael addition under solvent-free reaction conditions

Silicon-based thiourea (SiliaBond® Thiourea) (Si-THU), a heterogeneous catalyst, has been applied to the highly selective C-S bond formation via Michael addition of thiols to α,β-unsaturated carbonyl compounds under solvent-free conditions at 55–60°C. The thio-Michael addition products were obtained in an excellent yield under optimised conditions. This methodology involving a metal-free as well as a metal scavenger catalyst has been found to be an alternative method for the thio-Michael addition reaction.

[1]  P. Manivel,et al.  5-(4-Chlorophenyl)-3-(2-furyl)-1,2,4-triazolo[3,4-a]isoquinoline , 2010, Acta crystallographica. Section E, Structure reports online.

[2]  F. Nawaz Khan,et al.  Basic Alumina-Catalyzed, Solvent-Free Synthesis of Diversified Thioethers , 2010 .

[3]  S. Santra,et al.  Silica nanoparticles as a reusable catalyst: a straightforward route for the synthesis of thioethers, thioesters, vinyl thioethers and thio-Michael adducts under neutral reaction conditions , 2010 .

[4]  K. Jacobson.  Functionalized congener approach to the design of ligands for G protein-coupled receptors (GPCRs). , 2009, Bioconjugate chemistry.

[5]  S. Ng,,et al.  1-(4-Chlorophenyl)-2-phenyl-2-(3-phenyl-1-isoquinolylsulfanyl)ethanone , 2009, Acta crystallographica. Section E, Structure reports online.

[6]  S. Ng,,et al.  2-[2-(Cyclohexylcarbonyl)phenyl]-1-phenylethanone , 2009, Acta crystallographica. Section E, Structure reports online.

[7]  Atul Kumar,et al.  Amino acid catalyzed thio-Michael addition reactions , 2007 .

[8]  Gopal L. Khatik,et al.  Scope and Limitations of HClO4—SiO2 as an Extremely Efficient, Inexpensive, and Reusable Catalyst for Chemoselective Carbon—Sulfur Bond Formation. , 2007 .

[9]  Gopal L. Khatik,et al.  Scope and limitations of HClO4–SiO2 as an extremely efficient, inexpensive, and reusable catalyst for chemoselective carbon–sulfur bond formation , 2007 .

[10]  A. Shaabani,et al.  Tangstophosphoric acid (H3PW12O40): An efficient and eco-friendly catalyst for the one-pot synthesis of dihydropyrimidin-2(1H)-ones , 2006 .

[11]  B. Movassagh,et al.  Michael addition of thiols to α,β-unsaturated carbonyl compounds under solvent-free conditions , 2006 .

[12]  M. Jafarpour,et al.  ZrOCl2·8H2O/silica gel as a new efficient and a highly water–tolerant catalyst system for facile condensation of indoles with carbonyl compounds under solvent-free conditions , 2006 .

[13]  T. Gavin,et al.  A Mild and Highly Convenient Chemoselective Alkylation of Thiols Using Cs2CO3—TBAI. , 2006 .

[14]  T. Gavin,et al.  A mild and highly convenient chemoselective alkylation of thiols using Cs2CO3–TBAI , 2005 .

[15]  Sébastien Perrier,et al.  Macromolecular design via réversible addition-fragmentation chain transfer (RAFT)/Xanthates (MADIX) polymerization , 2005 .

[16]  C. Yao,et al.  Iodine-catalyzed Michael addition of mercaptans to α,β- unsaturated ketones under solvent-free conditions , 2005 .

[17]  B. Ranu,et al.  Catalysis by Ionic Liquid: A Simple, Green and Efficient Procedure for the Michael Addition of Thiols and Thiophosphate to Conjugated Alkenes in Ionic Liquid, [pmIm]Br. , 2004 .

[18]  B. Ranu,et al.  Catalysis by ionic liquid: a simple, green and efficient procedure for the Michael addition of thiols and thiophosphate to conjugated alkenes in ionic liquid, [pmIm]Br , 2004 .

[19]  M. Davis,et al.  Design and preparation of organic-inorganic hybrid catalysts. , 2002, Chemical reviews.

[20]  M. Bandini,et al.  Sequential one-pot InBr(3)-catalyzed 1,4- then 1,2-nucleophilic addition to enones. , 2002, The Journal of organic chemistry.

[21]  B. Benicewicz,et al.  Montmorillonite K 10-catalyzed regioselective addition of thiols and thiobenzoic acids onto olefins: an efficient synthesis of dithiocarboxylic esters , 2001 .

[22]  Sudalai,et al.  Phosphorus pentasulfide: A mild and versatile Catalyst/Reagent for the preparation of dithiocarboxylic esters , 2000, Organic letters.

[23]  T. Mitsudo,et al.  Metal-catalyzed carbon-sulfur bond formation. , 2000 .

[24]  T. Kondo,et al.  Metal-catalyzed carbon-sulfur bond formation. , 2000, Chemical reviews.

[25]  J. Falck,et al.  ALKYLTHIOETHER SYNTHESIS VIA IMIDAZOLE MEDIATED MITSUNOBU CONDENSATION , 1999 .

[26]  R. Mayadunne,et al.  A novel synthesis of functional dithioesters, dithiocarbamates, xanthates and trithiocarbonates , 1999 .

[27]  A. Padwa,et al.  Sigmatropic rearrangements in the allyl substituted oxazolinone system , 1981 .

[28]  S. Ōae,et al.  The reaction of diaryl disulfides with pyridine N-oxides☆ , 1968 .

[29]  R. Murray,et al.  P-phenylene-bis(cycloheptatrienylium cation), a stable dicarbonium ion☆ , 1965 .