76542-10-4Relevant academic research and scientific papers
Air-stable binuclear Titanium(IV) salophen perfluorobutanesulfonate with zinc power catalytic system and its application to C–S and C–Se bond formation
Wang, Lingxiao,Qiao, Jie,Wei, Jiancong,Liang, Zhiwu,Xu, Xinhua,Li, Ningbo
, (2020/01/08)
An air-stable μ-oxo-bridged binuclear Lewis acid of titanium(IV) salophen perfluorobutanesulfonate [{Ti(salophen)H2O}2O][OSO2C4F9]2 (1) was successfully synthesized by the reaction of TiIV(salophen)Cl2 with AgOSO2C4F9 and characterized by techniques such as IR, NMR and HRMS. This complex was stable open to air over a year, and exhibited good thermal stability and high solubility in polar organic solvents. The complex also had relatively strong acidity with a strength of 0.8 Ho ≤ 3.3, and showed high catalytic efficiency towards various C–S and C–Se bond formations in the presence of zinc power. This catalytic system affords a mild and efficient approach to synthesis of thio- and selenoesters, α-arylthio- and seleno-carbonyl compounds, and thio- and selenoethers.
Preparation method and application of novel ionic binuclear Schiff base titanium complex
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Paragraph 0046; 0047, (2018/04/03)
The invention provides a preparation method of a novel ionic binuclear Schiff base titanium complex and a synthetic method of applying the novel ionic binuclear Schiff base titanium complex to catalyze zinc powder and reduce disulfide or selenide to prepare sulfo(seleno) ester and dissymmetric sulfoether(selenide). The complex is a cationic binuclear Schiff base titanium complex, wherein titaniumatoms are bridged by oxygen atoms and are coordinated with a Schiff base ligand and a hydrone, and an ionic bond is formed by a cation part and an anion part of whole Schiff base titanium. The ionic binuclear Schiff base titanium complex is used as a catalyst, the zinc powder is used as a reducer, the disulfide(selenide) can be reduced and fractured, and the disulfide(selenide) can further and respectively react with anhydride, an alpha-bromo carbonyl compound and bromoalkane to prepare the sulfo(seleno) ester and the dissymmetric sulfoether(selenide). According to the preparation method provided by the invention, the defects that traditional lewis acid halide is deliquescent, an absolute solvent is used, conditions are strict and the like are overcome; an effective path for reducing the disulfide or selenide to prepare the sulfo(seleno) ester and the dissymmetric sulfoether(selenide) is provided, and the preparation method has the advantages of high yield, simpleness in operation andthe like.
Rapid and convenient thioester synthesis under phase-transfer catalysis conditions
Simion, Cristian,Hashimoto, Iwao,Mitoma, Yoshiharu,Simion, Alina Marieta,Egashira, Naoyoshi
experimental part, p. 2480 - 2488 (2011/02/23)
Various thioesters were obtained through an efficient phase-transfer catalysis method, by treating several thiophenols with different acyl chlorides, in a biphasic system composed of 10% aqueous NaOH and dichloromethane in the presence of tetrabutylammonium chloride. The thiolation reaction was complete in only 5 minutes, at 0C. Taylor & Francis Group, LLC.
Air-stable, cationic, Lewis acid, titanocene perfluorooctanesulfonate- catalyzed reductive cleavage of S-S bond by zinc and its application in synthesis of thioesters
Qiu, Ren Hua,Xu, Xin Hua,Li, Yin Hui,Shao, Ling Ling,Zhang, Guo Ping,An, De Lie
experimental part, p. 3309 - 3314 (2010/12/24)
Titanocene perfluorooctanesulfonate is air-stable complex. In the presence of 10mol% of the complex, reductive cleavage of an S-S bond by zinc in commercial tetrahydrofuran at room temperature led to nucleophilic sulfur anion species, which reacted with acid anhydrides to afford thioesters in good to excellent yields. Copyright
KF/Al2O3 catalysed synthesis of thiol esters from N-acylphthalimides and thiols
Movassagh, Barahman,Zakinezhad, Yousef
, p. 369 - 370 (2007/10/03)
A new method for the preparation of thiol esters from N-acylphthalimides and thiols in the presence of KF/Al2O3 is introduced.
Kinetics and mechanism of the aminolysis of aryl propanedithioates in acetonitrile
Hyuck Keun Oh,Sun Kyung Kim,Hai Whang Lee,Lee
, p. 313 - 317 (2007/10/03)
The kinetics and mechanism of the aminolysis of aryl proanedithioates with benzylamines are investigated in acetonitrile at - 35.0 °C. A large magnitude of the Hammett (ρx and ρz) and Broensted (βx and βz) coefficients and exceptionally large cross-interaction constant ρxz(= 3.5) are consistent with a stepwise mechanism in which leaving group expulsion from an intermediate, T±, is the rate-determining step. The faster rates observed for dithio esters (I1) than for thio esters (I), and the validity of the reactivity-selectivity principle (RSP) are also in line with the mechanism proposed. The kH/kD values (= 1.0-1.8) determined with deuterated benzylamines (XC6H4CH2ND2) and the activation parameters, ΔH≠(?8 kcal mol-1) and ΔS≠(= -16 to -23 e.u.), suggest that proton transfer occurs concurrently with leaving group departure in the transition state.
A convenient one-pot synthesis of thiol esters from disulfides using a Zn/AlCl3 system
Movassagh,Lakouraj,Fadaei
, p. 22 - 23 (2007/10/03)
A novel synthetic procedure for the direct preparation of thiol esters from various disulfides and symmetrical anhydrides using a Zn/AlCl3 system is described.
Kinetics and mechanism of the aminolysis of thiophenyl methylacetates in acetonitrile
Oh, Hyuck Keun,Yang, Jin Hee,Cho, In Ho,Lee, Hai Whang,Lee, Ikchoon
, p. 485 - 490 (2007/10/03)
The aminolysis of Z-thiophenyl methylacetates (C2H5C(double bond O)SC6H4Z) with X-benzylamines in acetonitrile has been investigated at 45 °C. The reaction is found to proceed by a stepwise mechanism in which the rate-determining step is the breakdown of the zwitterionic tetrahedral intermediate, T±, with possibly a hydrogen-bonded four-center-type transition state. These mechanistic conclusions are drawn based on (i) the large magnitude of βX (= 1.2 to approximately 2.5) and βz (= -0.9 to approximately -1.5), (ii) the normal kinetic isotope effects (kH/kD?1.2) involving deuterated benzylamines (XC6H4CH2ND2), (iii) a large positive ρxz (= 2.4) and (iv) adherence to the reactivity-selectivity principle in all cases. The extremely large βX (βnuc) values can be accounted for by the loss of a strong localized cationic charge on the N atom of benzylamines in the expulsion from the T±. The pKa° (≥10.0) is high due to a large ratio of the expulsion rates of the amine (k-a) to thiophenolate (kb) (k-a/kb) from the T±.
Flash vacuum pyrolysis of stabilised phosphorus ylides. Part 15. Generation of alkoxycarbonyl(sulfenyl)carbenes and their intramolecular insertion to give alkenyl sulfides
Aitken, R. Alan,Armstrong, Jill M.,Drysdale, Martin J.,Ross, Fiona C.,Ryan, Bruce M.
, p. 593 - 604 (2007/10/03)
A range of 18 alkoxycarbonyl sulfinyl phosphorus ylides 9 have been prepared and their behaviour upon flash vacuum pyrolysis (FVP) at 600 deg C examined. For R1 = H, Me and Et they lose Ph3PO and in some cases Ph3P to give mixtures of products including the alkenyl sulfides 10, the sulfides 11, the disulfides 12 and the thioesters 14. The alkenyl sulfides 10 most likely arise from intramolecular insertion of the alkoxycarbonyl sulfenyl carbenes resulting from loss off Ph3PO to produce β-lactones which then lose CO2 and this is supported by the results from 13C labelled ylides. Possible mechanisms for the formation of 11 and 14 are also presented and the feasibility of various steps has been examined by preparation and pyrolysis of the proposed intermediates. In contrast, pyrolysis of the ylides 9 where R1 = Ph and the tert-butoxycarbonyl ylides 30 leads mainly to complete fragmentation with loss of Ph3PO and benzyl alcohol or 2-methylpropan-2-ol and does not give any useful sulfur-containing products. Four alkoxy-carbonyl sulfonyl diazo compounds 33 have been prepared and in three cases they give the alkenyl sulfones 34 upon FVP at 400 deg C, probably by an intramolecular insertion and decarboxylation process analogous to the formation of 10 from 9. On the other hand the alkoxycarbonyl carbenes produced by FVP of the amino acid-derived diazo compounds 35 undergo alternative proocesses with no sign of β-lactone formation. Fully assigned 13C NMR data are presented for 13 of the ylides.
A SIMPLE SYNTHESIS OF THIOL ESTERS FROM COPPER-I-MERCAPTIDES AND ACYL CHLORIDES
Reissig, Hans-Ulrich,Scherer, Bernadette
, p. 4259 - 4262 (2007/10/02)
Thiol esters are obtained from acyl chlorides and copper-I-mercaptides in excellent yields.
