25855-25-8Relevant academic research and scientific papers
Cyanide-Free Synthesis of Air Stable N-Substituted Li and K Cyanamide Salts from Tetrazoles. Applications toward the Synthesis of Primary and Secondary Cyanamides as Precursors to Amidines
Duchamp, Edouard,Hanessian, Stephen
, p. 8487 - 8491 (2020/11/12)
A practical two-step synthesis of N,N′-disubstituted cyanamides consists in the low-temperature metalation of N-substituted 5H-tetrazoles that undergo spontaneous cycloreversion at 0 °C releasing dinitrogen, and forming N-metalated cyanamides that can be reacted in situ with a variety of electrophiles. Remarkably, the N-substituted Li and K cyanamides are air stable white solids at room temperature. Addition of lithium organometallics to the N,N′-disubstituted cyanamides provides a new method for accessing N,N′-disubstituted amidines.
5-(Cyano)dibenzothiophenium Triflate: A Sulfur-Based Reagent for Electrophilic Cyanation and Cyanocyclizations
Li, Xiangdong,Golz, Christopher,Alcarazo, Manuel
supporting information, p. 9496 - 9500 (2019/06/27)
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.
Synthesis of Cyanamides via a One-Pot Oxidation-Cyanation of Primary and Secondary Amines
Kuhl, Nadine,Raval, Saurin,Cohen, Ryan D.
supporting information, p. 1268 - 1272 (2019/03/07)
An operationally simple oxidation-cyanation method for the synthesis of cyanamides is described. The procedure utilizes inexpensive and commercially available N-chlorosuccinimide and Zn(CN)2 as reagents to avoid direct handling of toxic cyanogen halides. It is demonstrated to be amenable for the cyanation of a variety of primary and secondary amines and aniline derivatives as well as a complex synthetic intermediate en route to verubecestat (MK-8931). Additionally, kinetic measurements and other control experiments are reported to shed light onto the mechanism of this cyanation reaction.
Deoxycyanamidation of Alcohols with N-Cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS)
Ayres, James N.,Ashford, Matthew W.,St?ckl, Yannick,Prudhomme, Vassili,Ling, Kenneth B.,Platts, James A.,Morrill, Louis C.
supporting information, p. 3835 - 3838 (2017/07/26)
The first one-pot deoxycyanamidation of alcohols has been developed using N-cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS) as both a sulfonyl transfer reagent and a cyanamide source, accessing a diverse range of tertiary cyanamides in excellent isolated yields. This approach exploits the underdeveloped desulfonylative (N-S bond cleavage) reactivity pathway of NCTS, which is more commonly employed for electrophilic C- and N-cyanation processes.
Transition-metal free N-arylation of cyanamides by diaryliodonium triflates in aqueous media
Li, Jihui,Zheng, Xinyi,Li, Wei,Zhou, Wei,Zhu, Wen,Zhang, Yucang
supporting information, p. 77 - 80 (2016/01/12)
An operationally simple protocol is established for the synthesis of disubstituted cyanamides through the transition-metal free N-arylation of cyanamides by diaryliodonium triflates in aqueous media. Both alkyl and aryl cyanamides are well compatible with the mild reaction conditions. The one-pot synthesis of ureas is also possible through sequential arylation and hydrolysis of cyanamides, diaryliodonium triflates and H2O with good yields.
A simple method for the electrophilic cyanation of secondary amines
Chen, Chuo,Zhu, Chen,Xia, Ji-Bao
supporting information, p. 247 - 249 (2014/01/23)
Bleach oxidizes trimethylsilyl cyanide to generate an electrophilic cyanating reagent that readily reacts with an amine nucleophile. This oxidative N-cyanation reaction allows for the preparation of disubstituted cyanamides from amines without using highly toxic cyanogen halides.
One-pot synthesis of 1-substituted-5-alkylselanyl-1H-tetrazoles from isoselenocyanates: Unexpected formation of N-alkyl-N-arylcyanamides and (Z)-Se-alkyl-N-cyano-N,N′-diarylisoselenoureas
Karabanovich, Galina,Roh, Jaroslav,Padělková, Zdeňka,Novák, Zdeněk,Vávrová, Kate?ina,Hrabálek, Alexandr
, p. 8798 - 8808 (2013/09/23)
1-Substituted-5-alkylsulfanyl-1H-tetrazoles are well known class of organic substances with various applications in medicinal chemistry or photographic industry. Their selenium analogues, 1-substituted-5-alkylselanyl-1H-tetrazoles are, however, much less explored because of the lack of suitable methods for their preparation. In this work we investigated the synthesis of 1-alkyl/aryl-5-alkylselanyl-1H-tetrazoles from synthetically available alkyl/arylisoselenocyanates. One-pot reactions of arylisoselenocyanates with sodium azide and alkylating agent led to the target 5-alkylselanyl-1-aryl-1H- tetrazoles but also to interesting side products, namely N-alkyl-N- arylcyanamides and (Z)-Se-alkyl-N-cyano-N,N′-diarylisoselenoureas. Nevertheless, when alkylisoselenocyanates were utilized as the substrates, the reactions led exclusively to the formation of 1-alkyl-5-alkylselanyl-1H- tetrazoles in good yields. This simple one-pot procedure brings new possibilities for the preparation of variously substituted selenium compounds. It also opens the way to further investigations of selenium isosteres of the widely utilized 5-thiotetrazole moiety in biomedical applications.
Modification of the Tiemann rearrangement: One-pot synthesis of N,N-disubstituted cyanamides from amidoximes
Bakunov, Stanislav A.,Rukavishnikov, Alexey V.,Tkachev, Alexey V.
, p. 1148 - 1159 (2007/10/03)
A three-stage one-pot synthetic procedure for transformation of amidoximes to N,N-disubstituted cyanamides in 70-92% yield is described.
