66907-51-5Relevant academic research and scientific papers
Sulfuryl Fluoride Promoted Thiocyanation of Alcohols: A Practical Method for Preparing Thiocyanates
Zhang, Guofu,Xuan, Lidi,Zhao, Yiyong,Ding, Chengrong
supporting information, p. 1413 - 1417 (2020/10/02)
A novel SO 2F 2-promoted thiocyanation method for the one-step synthesis of thiocyanates through C-O bond cleavage of readily available alcohols with ammonium thiocyanate as the thiocyanating agent was developed. The method avoids the use of additional catalyst, and a variety of (hetero)arene, alkene and aliphatic alcohols reacted with high efficiency in ethyl acetate under mild conditions to afford the corresponding thiocyanates in excellent to quantitative yields with broad functional-group compatibility.
Method for preparing organic thiocyanide
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Paragraph 0030-0033, (2020/05/01)
The invention relates to a method for preparing organic thiocyanide. The method comprises the following steps: mixing a benzyl alcohol compound (I) as described in the specification, thiocyanate, an alkaline substance and an organic solvent, carrying out a reaction at 25-50 DEG C for 3-6 hours in an SO2F2 atmosphere, and carrying out after-treatment on a reaction solution to obtain organic thiocyanide (II) as described in the specification. According to the invention, cheap, easily available and environment-friendly SO2F2 is used as an accelerant to efficiently promote preparation of organic thiocyanide from alcohol and thiocyanate, so the step that halogen is introduced into a preset position of a molecular structure in advance in a traditional production process is omitted; and the method is applicable to a wide range of substrates, can prepare corresponding organic thiocyanide at a high yield, is simple in operation process, and is suitable for large-scale preparation.
One-pot synthesis of (ethoxycarbonyl)difluoromethylthioethers from thiocyanate sodium and ethyl 2-(trimethylsilyl)-2,2-difluoroacetate (TMS-CF2CO2Et)
Xu, Lijun,Wang, Hongyu,Zheng, Changwu,Zhao, Gang
, p. 6057 - 6066 (2017/09/23)
An efficient one-pot cascade methodology for the synthesis of (ethoxycarbonyl)difluoromethyl thioethers is described. Benzyl, allyl, alkyl halides or diazonium salts as the starting materials together with thiocyanate sodium and TMS-CF2CO2Et in the presence of CsF or NaOAc afford a variety of the fluoroalkylthiolated products in moderate to good yields.
Synthetic scope, computational chemistry and mechanism of a base induced 5-endo cyclization of benzyl alkynyl sulfides
Motto, John M.,Castillo, álvaro,Greer, Alexander,Montemayer, Laura K.,Sheepwash, Erin E.,Schwan, Adrian L.
supporting information; experimental part, p. 1002 - 1010 (2011/03/19)
We present an experimental and computational study of the reaction of aryl substituted benzyl 1-alkynyl sulfides with potassium alkoxide in acetonitrile, which produces 2-aryl 2,3-dihydrothiophenes in poor to good yields. The cyclization is most efficient with electron withdrawing groups on the aromatic ring. Evidence indicates there is rapid exchange of protons and tautomerism of the alkynyl unit prior to cyclization. Theoretical calculations were also conducted to help rationalize the base induced 5-endo cyclization of benzyl 1-propynyl sulfide (1a). The potential energy surface was calculated for the formation of 2,3-dihydrothiophene in a reaction of benzyl 1-propynyl sulfide (1a) with potassium methoxide. Geometries were optimized with CAM-B3LYP/6-311+G(d,p) in acetonitrile with the CPCM solvent model. It is significant that the benzyl propa-1,2-dien-1-yl sulfane (6) possessed a lower benzylic proton affinity than the benzyl prop-2-yn-1-yl sulfane (8) thus favoring the base induced reaction of the former. From benzyl(propa-1,2-dien-1- yl sulfane (6), 2,3-dihydrothiophene can be formed via a conjugate base that undergoes 5-endo-trig cyclization followed by a protonation step.
Substitution Reactions toward 2-Nitrobenzyl Pseudohalides. The Crystal Structure of 2-Nitrobenzyl Tellurocyanate
Grung, Knut Eric,Roemming, Christian,Songstad, Jon
, p. 518 - 526 (2007/10/02)
The reactions between 2-nitrobenzyl pseudohalides, 2-NO2-PhCH2XCN, and pseudohalide ions, NCX- (X = S, Se or Te) have been studied kinetically in acetonitrile at 25.0 deg C.The reactions proceed through nucleophilic attack at the methylene carbon atom, forming exclusively the exchange products.The average nucleophilicity order, NCTe- >> NCSe- > NCS-, and the average leaving group order, NCTe- >/= NCSe- >/= NCS-, lead to a carbon basicity order NCTe- > NCSe- >/= NCS-, which is confirmed with equilibrium studies.A crystal structure determination of 2-nitrobenzyl tellurocyanate at ca. 135 deg C has revealed that the TeCN group is syn-clinal (gauche) to the C(CH2)-C(Ar) bond with a torsion angle of -48.5(5) deg.The TeCC plane forms an angle of 103.4(5) deg with the phenyl ring plane.In this conformation the steric influence of the 2-NO2 group in substitution reactions at the methylene carbon atom will be negligible except for bulky nucleophiles.The tellurium atom forms two fairly strong intermolecular bonds to nitrogen atoms from neighbouring tellurocyanate groups, viz. 2.889(6) Angstroem trans to the cyano group and 3.382(6) Angstroem trans to the methylene group.In the crystalline state the compound may be considered both as a tellurium(II) complex and as an organic pseudohalide.No intermolecular tellurium-oxygen contacts could be observed.
Correlation pKa - activitee catalitique des thiols dans la reeaction d'hydrolyse de l'aceetate de p-nitropheenyle
Brembilla, Alain,Roizard, Denis,Schoenleber, Jacqueline,Lochon, Pierre
, p. 2330 - 2336 (2007/10/02)
The kinetic study of the hydrolysis of p-nitrophenylacetate in the presence of primary thiols indicates the thiolate anion as the sole catalytic species.Comparison of the true second order constants (kRS-) reveals that purely aliphatic primary thiols behave differently from aromatic α-substituted primary thiols.In the latter group a correlation can be established between the true second order rate constants and the pKSH values by means of the Broensted equation log kRS- = βpKSH + C, with β equal to 0.40 and C equal to -0.85.
