4148-93-0Relevant academic research and scientific papers
Nanolayered cobalt-molybdenum sulphides (Co-Mo-S) catalyse borrowing hydrogen C-S bond formation reactions of thiols or H2S with alcohols
Corma, Avelino,Sorribes, Iván
, p. 3130 - 3142 (2019/03/13)
Nanolayered cobalt-molybdenum sulphide (Co-Mo-S) materials have been established as excellent catalysts for C-S bond construction. These catalysts allow for the preparation of a broad range of thioethers in good to excellent yields from structurally diverse thiols and readily available primary as well as secondary alcohols. Chemoselectivity in the presence of sensitive groups such as double bonds, nitriles, carboxylic esters and halogens has been demonstrated. It is also shown that the reaction takes place through a hydrogen-autotransfer (borrowing hydrogen) mechanism that involves Co-Mo-S-mediated dehydrogenation and hydrogenation reactions. A novel catalytic protocol based on the thioetherification of alcohols with hydrogen sulphide (H2S) to furnish symmetrical thioethers has also been developed using these earth-abundant metal-based sulphide catalysts.
Lithium-Catalyzed Thiol Alkylation with Tertiary and Secondary Alcohols: Synthesis of 3-Sulfanyl-Oxetanes as Bioisosteres
Croft, Rosemary A.,Mousseau, James J.,Choi, Chulho,Bull, James A.
supporting information, p. 818 - 821 (2017/12/26)
3-Sulfanyl-oxetanes are presented as promising novel bioisosteric replacements for thioesters or benzyl sulfides. From oxetan-3-ols, a mild and inexpensive Li catalyst enables chemoselective C?OH activation and thiol alkylation. Oxetane sulfides are formed from various thiols providing novel motifs in new chemical space and specifically as bioisosteres for thioesters due to their similar shape and electronic properties. Under the same conditions, various π-activated secondary and tertiary alcohols are also successful. Derivatization of the oxetane sulfide linker provides further novel oxetane classes and building blocks. Comparisons of key physicochemical properties of the oxetane compounds to selected carbonyl and methylene analogues indicate that these motifs are suitable for incorporation into drug discovery efforts.
Preparation of Quaternary Centers via Nickel-Catalyzed Suzuki-Miyaura Cross-Coupling of Tertiary Sulfones
Ariki, Zachary T.,Maekawa, Yuuki,Nambo, Masakazu,Crudden, Cathleen M.
supporting information, p. 78 - 81 (2018/01/17)
We describe the development of a nickel-catalyzed Suzuki-Miyaura cross-coupling of tertiary benzylic and allylic sulfones with arylboroxines. A variety of tertiary sulfones, which can easily be prepared via a deprotonation-alkylation route, were reacted to afford symmetric and unsymmetric quaternary products in good yields. We highlight the use of either BrettPhos or Doyle's phosphines as effective ligands for these challenging desulfonative coupling reactions. The utility of this methodology was demonstrated in the concise synthesis of a vitamin D receptor modulator analogue.
Highly Efficient and Chemoselective Tertiary and Secondary Benzylation of Thiols Catalyzed by Indium(III) Triflate
Kuciński, Krzysztof,Hreczycho, Grzegorz
, p. 5572 - 5581 (2017/10/13)
Several examples of nucleophilic substitution reactions of compounds that have good leaving groups have been previously reported, but the direct use of simple alcohols still remains a challenge because of the poor leaving ability of the hydroxy group. Herein, an efficient and highly chemoselective method for the S-benzylation of a wide range of aromatic and aliphatic thiols has been accomplished in the presence of catalytic amounts (0.1–0.2 mol-%) of indium(III) triflate. Our approach is atom efficient (water is the only byproduct) and suitable to obtain the corresponding unsymmetrical thioethers in excellent yields (up to 99 %). The low loading of catalyst that are needed to obtain extraordinarily high chemoselectivities and the generality of the reaction make this approach unique.
Desulfurative Chlorination of Alkyl Phenyl Sulfides
Canestrari, Daniele,Lancianesi, Stefano,Badiola, Eider,Strinna, Chiara,Ibrahim, Hasim,Adamo, Mauro F. A.
supporting information, p. 918 - 921 (2017/02/26)
The chlorination of readily available secondary and tertiary alkyl phenyl sulfides using (dichloroiodo)benzene (PhICl2) is reported. This mild and rapid nucleophilic chlorination is extended to sulfa-Michael derived sulfides, affording elimination-sensitive β-chloro carbonyl and nitro compounds in good yields. The chlorination of enantioenriched benzylic sulfides to the corresponding inverted chlorides proceeds with high stereospecificity, thus providing a formal entry into enantioenriched chloro-Michael adducts. A mechanism implying the formation of a dichloro-λ4-sulfurane intermediate is proposed.
Electrophilic phosphonium cations catalyze hydroarylation and hydrothiolation of olefins
Pérez, Manuel,Mahdi, Tayseer,Hounjet, Lindsay J.,Stephan, Douglas W.
supporting information, p. 11301 - 11304 (2015/07/07)
Electrophilic phosphonium cations (EPCs) are efficient main group catalysts for the hydroarylation of olefins under mild conditions, providing a facile route to substituted aniline, bis-arylamine, phenol, furan, thiophene, pyrrole, and indole derivatives.
Iron-catalysed Markovnikov hydrothiolation of styrenes
Cabrero-Antonino, Jose R.,Leyva-Perez, Antonio,Corma, Avelino
, p. 678 - 687 (2012/04/18)
The bis(triflimide)iron(III) salt catalyzes the hydrothiolation of styrenes in a Markovnikov fashion with good selectivities and high yields. After isolation, different benzylic thioethers are obtained. This iron(III) catalyst is unique in terms of regioselectivity and represents a sustainable and economic alternative to those processes based on stoichiometric reagents. Copyright
Regioselective cobalt-catalyzed addition of sulfides to unactivated alkenes
Girijavallabhan, Vinay,Alvarez, Carmen,Njoroge, F. George
experimental part, p. 6442 - 6446 (2011/09/16)
A novel method to synthesize tertiary alkyl/aryl sulfides in a mild and regioselective manner from unactivated alkenes using cobalt catalysis is described. The methodology is compatible with sensitive functionalities and is successful with several different types of alkenes and sulfides.
A Facile Method for Synthesis of Alkyl Phenyl Selenides. The Reaction of Diphenyl Diselenide with Oxygen-containing Compounds Using La/Me 3SiCl/cat.I2/cat.CuI System
Nishino, Toshiki,Nishiyama, Yutaka,Sonoda, Noboru
, p. 918 - 919 (2007/10/03)
Alcohols, ethers, and esters were directly converted to the corresponding alkyl phenyl selenides by the reaction of diphenyl diselenide and the La/Me 3SiCl/cat.I2/cat.CuI. It was suggested that alkyl phenyl sele
Thermolysis of free-radical initiators: tert-butylazocumene and its 1,3- and 1,4-bisazo and 1,3,5-trisazo analogues
Engel,Pan,Ying,Alemany
, p. 3706 - 3715 (2007/10/03)
Four tert-butylazocumenes (4-7) were prepared from the corresponding cyanobenzenes, and their nitrogen evolution kinetics and products were analyzed. In combination with TEMPO, the simplest compound, tert-butylazocumene (4), shows promise as a "one-radical" initiator of styrene polymerization. The ABNO-trapped cumyl radical 29 is a particularly stable trialkylhydroxylamine, whose thermolysis half-life is 2.1 h at 150 °C. Taking advantage of this stability, we trapped the cumyl radical centers from 7 to afford tris adduct 32a. While the behavior of the meta bisazoalkane 6 can be mostly predicted from that of 4, the para isomer 5 exhibits both unusual products and kinetics, attributed to the formation of quinodimethane 33 via azo-containing radical 34. In fact, flash vacuum pyrolysis of 5 allowed observation of the 1H and 13C NMR spectra of 33, whose persistence even at ambient temperature showed that this quinodimethane is far more stable than the parent 36. Finally, evidence is presented that 7 is an initiator of star polymerization.
