100954-03-8Relevant articles and documents
Dramatic enhancement of catalytic activity in an ionic liquid: Highly practical Friedel-Crafts alkenylation of arenes with alkynes catalyzed by metal triflates
Song, Choong Eui,Jung, Da-Un,Choung, Su Yhen,Roh, Eun Joo,Lee, Sang-Gi
, p. 6183 - 6185 (2004)
A simple and highly efficient method for the Friedel-Crafts alkenylation of aromatic compounds has been developed by using a metal triflate (OTf) catalyst in an ionic liquid (see scheme, bmim = 1-butyl-3-methylimidazolium). Not only is the catalytic activity significantly enhanced in the ionic liquid and by-product formation decreased, but some reactions that were not possible in conventional organic solvents were shown to proceed smoothly.
Organocatalytic trans Phosphinoboration of Internal Alkynes
Fritzemeier, Russell G.,Nekvinda, Jan,Rosenblum, Carol Ann,Santos, Webster L.,Slebodnick, Carla,Vogels, Christopher M.,Westcott, Stephen A.
, p. 14358 - 14362 (2020)
We report the first trans phosphinoboration of internal alkynes. With an organophosphine catalyst, alkynoate esters and the phosphinoboronate Ph2P-Bpin are efficiently converted into the corresponding trans-α-phosphino-β-boryl acrylate products in moderate to good yield with high regio- and Z-selectivity. This reaction operates under mild conditions and demonstrates good atom economy, requiring only a modest excess of the phosphinoboronate. X-ray crystallography experiments allowed structural assignment of the unprecedented and densely functionalized (Z)-α-phosphino-β-boryl acrylate products.
Tandem trifluoromethylthiolation/aryl migration of aryl alkynoates to trifluoromethylthiolated alkenes
Li, Huan,Liu, Shuai,Huang, Yangen,Xu, Xiu-Hua,Qing, Feng-Ling
, p. 10136 - 10139 (2017)
A trifluoromethylthiolation initiated aryl migration of aryl alkynoates was disclosed. This protocol employs AgSCF3 as the SCF3 source and MeCN as both the solvent and the hydrogen source. This provides a new access to trifluoromethylthiolated alkenes from readily available substrates and reagents.
Atom Transfer Oxidative Radical Cascade of Aryl Alkynoates towards 1,1-Dichalcogenide Olefins
Sahoo, Harekrishna,Ramakrishna, Isai,Mandal, Anup,Baidya, Mahiuddin
, p. 4549 - 4552 (2019)
An oxidative trifunctionalization of aryl alkynoates has been devised via the chalcogenide radical triggered intramolecular 1,4-aryl migration/decarboxylation cascade to prepare 1,1-dichalcogenide tetrasubstituted alkenes in high yields (up to 98 %). This operationally simple reaction proceeds under metal-free conditions, can be executed on gram scale, and highlights formal 1,1-difunctionalization of alkynes. Synthetic potential of this protocol was demonstrated through a twofold cascade rearrangement to access highly conjugated tetra-selenylated alkenes along with a cross-dehydrogenative annulation to prepare fluorene derivative.
Metal-Free Synthesis of Selenodihydronaphthalenes by Selenoxide-Mediated Electrophilic Cyclization of Alkynes
An, Shaoyu,Li, Pingfan,Zhang, Zhong
, p. 3059 - 3070 (2021/07/22)
A transition-metal-free, selenium mediated electrophilic cyclization reaction was realized through a one-pot procedure between simple alkynes and triflic anhydride-activated selenoxides to give selenium containing dihydronaphthalene products. This method gave good to very high yields for all products, including selenium-substituted phenanthrene, dihydroquinoline, 2H-chromene, and coumarin, which can be further transformed to other functionalized compounds.
Copper-catalyzed cascade radical cyclization of alkynoates: Construction of aryldifluoromethylated coumarins
Chen, Zhiwei,Huang, Xiaoxiao,Tang, Wei,Zeng, Piaopiao
supporting information, p. 10223 - 10227 (2021/12/10)
A mild and simple method is reported for the construction of 3-difluoroarylmethylated coumarins using α,α-difluoroarylacetic acids as an easily handled difluoromethyl source in reaction with ester 3-arylpropiolates under the promotion of copper. The reaction involves a proposed radical-triggered domino decarboxylative aryldifluoromethylation/5-exo cyclization/ester migration process that directly forms Csp2-CF2Ar and C-C bonds with good functional group tolerance. This journal is
Chlorinative Cyclization of Aryl Alkynoates Using NCS and 9-Mesityl-10-methylacridinium Perchlorate Photocatalyst
Pramanik, Milan,Mathuri, Ashis,Sau, Sudip,Das, Monojit,Mal, Prasenjit
supporting information, p. 8088 - 8092 (2021/10/12)
In a chlorinative cyclization, Mes-Acr-MeClO4 acted as a visible-light photocatalyst to obtain 3-chlorocoumarins from aryl alkynoates and N-chlorosuccinimide (NCS). The radical initiated reaction proceeded in a cascading manner via Cl- addition to alkynoa
trans-Selective hydrocyanation of ynoates, ynones and ynoic acids catalyzed by nucleophilic phosphines
Meyer, Maximilian,Peri?, Milica,Sch?mberg, Fritz,Vilotijevi?, Ivan
supporting information, (2021/10/04)
trans-Selective hydrocyanation of ynoates and ynones in the presence of TMSCN and an alcohol additive are catalyzed by nucleophilic phosphines. The trisubstituted E-olefin products of anti-addition of hydrogen cyanide to the alkyne are produced with high regio- and stereoselectivity. The alcohol additive reacts with TMSCN to produce hydrogen cyanide in situ. Ynoic acids undergo the phosphine catalyzed hydrocyanation in the presence of TMSCN under aprotic conditions only. In these reactions, TMSCN reacts with the acid to generate hydrogen cyanide and the silyl ester which, unlike the acid, undergoes phosphine catalyzed hydrocyanation and gives the stereo-defined E-2-cyano-acrylic acids after work up.
Cyclization of aryl 3-aryl propynoates into 4-arylcoumarins catalyzed by cyclometalated Platinum(II) complexes
Zaitceva, Olesia,Bénéteau, Valérie,Ryabukhin, Dmitry S.,Eliseev, Ivan I.,Kinzhalov, Mikhal A.,Louis, Benoit,Vasilyev, Aleksander V.,Pale, Patrick
supporting information, (2020/03/05)
Cyclometalated (ppy)PtII complexes (ppy = 2-phenylpyridinato-C2,N) catalyze the intramolecular cyclization of aryl propynoates to form coumarins and benzocoumarins. The complex [(ppy)PtCl(MeCN)] (5 mol %) was the most active and effi
Ynamide-Mediated Intermolecular Esterification
Wang, Xuewei,Yang, Yang,Zhao, Yongli,Wang, Sheng,Hu, Wenchang,Li, Jinmei,Wang, Zihao,Yang, Fengling,Zhao, Junfeng
, p. 6188 - 6194 (2020/05/26)
An ynamide-mediated one-pot, two-step intermolecular esterification via the condensation of carboxylic acids with nucleophilic hydroxyl species was reported. A broad substrate scope with respect to carboxylic acids, alcohols, and phenols was observed. The α-acyloxyenamide intermediates formed by the addition of carboxylic acids to ynamides proved to be effective acylating reagents for the esterification of alcohol and phenol derivatives with the assistance of base catalysis. Notably, the racemization of the α-chiral center of carboxylic acids can be avoided.
