- 5-(Cyano)dibenzothiophenium Triflate: A Sulfur-Based Reagent for Electrophilic Cyanation and Cyanocyclizations
-
The synthesis of 5-(cyano)dibenzothiophenium triflate 9, prepared by activation of dibenzo[b,d]thiophene-5-oxide with Tf2O and subsequent reaction with TMSCN is reported, and its reactivity as electrophilic cyanation reagent evaluated. The scalable preparation, easy handling and broad substrate scope of the electrophilic cyanation promoted by 9, which includes amines, thiols, silyl enol ethers, alkenes, electron rich (hetero)arenes and polyaromatic hydrocarbons, illustrate the synthetic potential of this reagent. Importantly, Lewis acid activation of the reagent is not required for the transfer process. We additionally report herein biomimetic cyanocyclization cascade reactions, which are not promoted by typical electrophilic cyanation reagents, demonstrating the superior ability of 9 to trigger challenging transformations.
- Li, Xiangdong,Golz, Christopher,Alcarazo, Manuel
-
supporting information
p. 9496 - 9500
(2019/06/27)
-
- One-pot synthesis of (ethoxycarbonyl)difluoromethylthioethers from thiocyanate sodium and ethyl 2-(trimethylsilyl)-2,2-difluoroacetate (TMS-CF2CO2Et)
-
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.
- Xu, Lijun,Wang, Hongyu,Zheng, Changwu,Zhao, Gang
-
p. 6057 - 6066
(2017/09/23)
-
- Transition-metal-free synthesis of thiocyanato- or nitro-arenes through diaryliodonium salts
-
A transition-metal-free approach to facile synthesis of thiocyanato- and nitro-arenes was developed from KSCN (potassiumthiocyanate) or NaNO2with diaryliodonium salts in good yields under mild conditions. The reaction was compatible with a variety of sensitive functional substituents such as halides and nitro and ester groups. The usefulness of arylation products has been realized. (Formula Present).
- Li, Xiao-Hua,Li, Liang-Gui,Mo, Xue-Ling,Mo, Dong-Liang
-
supporting information
p. 963 - 970
(2016/07/07)
-
- General and practical formation of thiocyanates from thiols
-
A new method for the cyanation of thiols and disulfides using cyanobenziodoxol(on)e hypervalent iodine reagents is described. Both aliphatic and aromatic thiocyanates can be accessed in good yields in a few minutes at room temperature starting from a broad range of thiols with high chemioselectivity. The complete conversion of disulfides to thiocyanates was also possible. Preliminary computational studies indicated a low energy concerted transition state for the cyanation of the thiolate anion or radical. The developed thiocyanate synthesis has broad potential for various applications in synthetic chemistry, chemical biology and materials science.
- Frei, Reto,Courant, Thibaut,Wodrich, Matthew D.,Waser, Jerome
-
supporting information
p. 2662 - 2668
(2015/02/05)
-
- A mild copper-catalyzed aerobic oxidative thiocyanation of arylboronic acids with TMSNCS
-
A facile and efficient transformation of arylboronic acids to their corresponding aryl thiocyanates has been successfully developed. Based on the CuCl-catalyzed oxidative cross-coupling reaction between arylboronic acids and trimethylsilylisothiocyanate (TMSNCS) under oxygen atmosphere, the transformation can be readily conducted at ambient temperature. The newly-developed protocol provided a competitive synthetic approach to aryl thiocyanates that can tolerate a broad range of reactive functional groups and/or strong electron-withdrawing groups.
- Sun, Nan,Che, Liusheng,Mo, Weimin,Hu, Baoxiang,Shen, Zhenlu,Hu, Xinquan
-
supporting information
p. 691 - 696
(2015/02/19)
-
- Synthesis of aryl thiocyanates via copper-catalyzed aerobic oxidative cross-coupling between arylboronic acids and KSCN
-
A new protocol for the preparation of aryl thiocyanates by the cross-coupling reaction of arylboronic acids with KSCN salt is described. The coupling reaction was catalyzed by 20 mol% of copper acetate in the presence of 2.0 equivalents 4-methylpyridine serving both as ligand and base under 0.2 MPa of molecular oxygen. A variety of arylboronic acids, including those with substituents at ortho position, were suitable under the reaction conditions. Georg Thieme Verlag Stuttgart · New York.
- Sun, Nan,Zhang, Han,Mo, Weimin,Hu, Baoxiang,Shen, Zhenlu,Hu, Xinquan
-
supporting information
p. 1443 - 1447
(2013/07/26)
-