153749-89-4Relevant articles and documents
Enantioselective total syntheses of ropivacaine and its analogues
Shankaraiah, Nagula,Pilli, Ronaldo Aloise,Santos, Leonardo S.
, p. 5098 - 5100 (2008)
An alternative asymmetric synthesis of ropivacaine and analogues employing the 'cation pool' strategy and host/guest supramolecular co-catalysis approach is presented. In this study, chiral auxiliaries, several soft nucleophiles as well as one-pot conditions for anodic oxidation, followed by nucleophilic addition, have been applied.
Decarboxylative Cyanation of Aliphatic Carboxylic Acids via Visible-Light Flavin Photocatalysis
Ramirez, Nieves P.,K?nig, Burkhard,Gonzalez-Gomez, Jose C.
supporting information, (2019/03/08)
An operationally simple method is disclosed for the decarboxylative cyanation of aliphatic carboxylic acids at room temperature. Riboflavin tetraacetate, which is an inexpensive organic photocatalyst, promotes the oxidation of carboxylic acids upon visible-light activation. After decarboxylation, the generated radicals are trapped by TsCN, yielding the desired nitriles without any further additive, in a redox-neutral process. Importantly, this protocol can be adapted to flow conditions.
PROCESS FOR THE PRODUCTION OF COBIMETINIB
-
, (2019/05/22)
The present invention relates to a novel route of synthesis for the production of enantiomerically pure Cobimetinib, new intermediates in the synthesis of Cobimetinib and an amorphous Cobimetinib hemifumarate salt comprising a high salt content.
A metal-free direct C (sp3)-H cyanation reaction with cyanobenziodoxolones
Sun, Ming-Xue,Wang, Yao-Feng,Xu, Bao-Hua,Ma, Xin-Qi,Zhang, Suo-Jiang
, p. 1971 - 1975 (2018/03/23)
A metal-free protocol of direct C(sp3)-H cyanation with cyanobenziodoxolones functioning as both cyanating reagents and oxidants was developed. Unactivated substrates, such as alkanes, ethers and tertiary amines, were thereby transformed to the corresponding nitriles in moderate to high yields. Mechanistic studies indicated that the cyanation proceeded with two potential pathways, which is highly dependent on the substrates: (1) a free radical case for alkanes and ethers and (2) an oxidative case for tertiary amines.
C(sp3)?H Cyanation Promoted by Visible-Light Photoredox/Phosphate Hybrid Catalysis
Wakaki, Takayuki,Sakai, Kentaro,Enomoto, Takafumi,Kondo, Mio,Masaoka, Shigeyuki,Oisaki, Kounosuke,Kanai, Motomu
supporting information, p. 8051 - 8055 (2018/06/15)
Inspired by the reaction mechanism of photo-induced DNA cleavage in nature, a C(sp3)?H cyanation reaction promoted by visible-light photoredox/phosphate hybrid catalysis was developed. Phosphate radicals, generated by one-electron photooxidation of phosphate salt, functioned as a hydrogen-atom-transfer catalyst to produce nucleophilic carbon radicals from C(sp3)?H bonds with a high bond-dissociation energy. The resulting carbon radicals were trapped by a cyano radical source (TsCN) to produce the C?H cyanation products. Due to the high functional-group tolerance and versatility of the cyano group, the reaction will be useful for realizing streamlined building block syntheses and late-stage functionalization of drug-like molecules.
Room temperature decarboxylative cyanation of carboxylic acids using photoredox catalysis and cyanobenziodoxolones: a divergent mechanism compared to alkynylation
Le Vaillant, Franck,Wodrich, Matthew D.,Waser, Jér?me
, p. 1790 - 1800 (2017/03/09)
The one-step conversion of aliphatic carboxylic acids to the corresponding nitriles has been accomplished via the merger of visible light mediated photoredox and cyanobenziodoxolones (CBX) reagents. The reaction proceeded in high yields with natural and non-natural α-amino and α-oxy acids, affording a broad scope of nitriles with excellent tolerance of the substituents in the α position. The direct cyanation of dipeptides and drug precursors was also achieved. The mechanism of the decarboxylative cyanation was investigated both computationally and experimentally and compared with the previously developed alkynylation reaction. Alkynylation was found to favor direct radical addition, whereas further oxidation by CBX to a carbocation and cyanide addition appeared more favorable for cyanation. A concerted mechanism is proposed for the reaction of radicals with EBX reagents, in contrast to the usually assumed addition elimination process.
Decarboxylative alkynylation and cyanation of carboxylic acids using photoredox catalysis and hypervalent iodine reagents
Le Vaillant, Franck,Waser, Jér?me
, p. 226 - 230 (2017/06/27)
Alkynes and nitriles are important functional groups that serve as versatile building blocks in organic synthesis and find applications in material and medicinal sciences. A convenient and straightforward access to both classes of compounds under mild conditions is, therefore, highly desirable. Herein, we disclose the decarb-oxylative alkynylation and cyanation of broadly available carboxylic acids using photoredox catalysis and hyper-valent iodine reagents. Choices of both catalysts and reagents were crucial. Computational and experimental studies revealed two different possible mechanisms that are dictated by the oxidation potential of the reagents: radical for alkynylation, ionic for cyanation.
Photoinduced direct cyanation of C(sp3)-H bonds
Hoshikawa, Tamaki,Yoshioka, Shun,Kamijo, Shin,Inoue, Masayuki
, p. 874 - 887 (2013/05/09)
A general and practical synthetic protocol for the direct transformation of unreactive C(sp3)-H bonds to C(sp3)-CN bonds has been developed. The homolytic cleavage of the C-H bond is initiated by photo-excited benzophenone, and the resulting carbon radical subsequently reacts with tosyl cyanide to afford the corresponding nitrile in a highly efficient manner. The present methodology is widely applicable to various starting materials including ethers, alcohols, amine derivatives, alkanes, and alkylbenzenes. This newly developed C-H cyanation protocol provides a powerful tool for selective one-carbon elongation for the construction of architecturally complex molecules. Georg Thieme Verlag Stuttgart - New York.
Direct electrochemical α-cyanation of N-protected cyclic amines
Libendi, Samuel Shikuku,Demizu, Yosuke,Onomura, Osamu
experimental part, p. 351 - 356 (2009/03/12)
α-Cyanation of N-protected cyclic amines was achieved using a direct electrochemical method. Unsubstituted N-protected cyclic amines were easily cyanated at the α-position using an undivided cell in high yields; moreover, α-cyanation of α′-substituted pyrrolidine and α′-,β′- or γ-substituted piperidines smoothly proceeded in high yield and with high to excellent diastereoselectivity. α-Substituted N-cyano-pyrrolidines and -piperidines were also cyanated at the more substituted position (the α-position) using a divided cell with high yield and high regioselectivity.
Direct oxidative cyanation based on the concept of site isolation
Tajima, Toshiki,Nakajima, Atsushi
scheme or table, p. 10496 - 10497 (2009/02/05)
On the basis of the concept of site isolation, we have successfully demonstrated direct oxidative cyanation of various organic compounds, which even have higher oxidation potentials compared to that of cyanide, by using a polystyrene-supported quaternary ammonium cyanide. Copyright
