7621-89-8Relevant academic research and scientific papers
N-Heterocyclic carbene-nitrogen molybdenum catalysts for utilization of CO2
Chen, Fei,Tao, Sheng,Liu, Ning,Dai, Bin
, (2021/01/19)
Three new N-heterocyclic carbene-nitrogen molybdenum complex was synthesized, and its catalytic activity was evaluated in the cycloaddition of epoxides with CO2. The molybdenum complex combined with tetrabutyl ammonium iodide (TBAI) resulted in a catalytic system for efficient conversion of a wide range of terminal and internal epoxides under 80 °C and 5–7 bar pressure for CO2. The cooperative catalysis mechanism between molybdenum complex and TBAI was elucidated, in which molybdenum complex was used as Lewis acid, and TBAI was employed as nucleophilic reagent. In addition, the NHC-Mo catalytic system was also successfully applied for the direct carboxylation of terminal alkynes with CO2.
Organocatalytic Strategy for the Fixation of CO2via Carboxylation of Terminal Alkynes
Shi, Jun-Bin,Bu, Qingqing,Liu, Bin-Yuan,Dai, Bin,Liu, Ning
, p. 1850 - 1860 (2021/01/14)
An organocatalytic strategy for the direct carboxylation of terminal alkynes with CO2 has been developed. The combined use of a bifunctional organocatalyst and Cs2CO3 resulted in a robust catalytic system for the preparation of a range of propiolic acid derivatives in high yields with broad substrate scope using CO2 at atmospheric pressure under mild temperatures (60 °C). This work has demonstrated that this organocatalytic method offers a competitive alternative to metal catalysis for the carboxylation of terminal alkynes and CO2. In addition, this protocol was suitable for the three-component carboxylation of terminal alkynes, alkyl halides, and CO2.
Oxidant- and additive-free simple synthesis of 1,1,2-triiodostyrenes by one-pot decaroboxylative iodination of propiolic acids
Ghosh, Subhankar,Ghosh, Rajat,Chattopadhyay, Shital K.
supporting information, (2020/09/15)
A metal- and oxidant-free facile synthesis of a range of 1,1,2-triiodostryrene derivatives has been developed which utilizes a simple decarboxylative triiodination of propiolic acids using molecular iodine and sodium acetate in a one-pot manner. Electron-
Visible light induced 3-position-selective addition of arylpropiolic acids with ethersviaC(sp3)-H functionalization
Luo, Jun,Wan, Zi-Juan,Yuan, Xiao-Feng
supporting information, p. 3258 - 3262 (2020/05/14)
Although the 2-position-selective decarboxylative coupling or addition of arylpropiolic acids with cyclic ethers has been intensively investigated, selective functionalization of arylpropiolic acids at the 3-position is still a big challenge. Herein, an i
Visible Light-Catalyzed Decarboxylative Alkynylation of Arenediazonium Salts with Alkynyl Carboxylic Acids: Direct Access to Aryl Alkynes by Organic Photoredox Catalysis
Yang, Liangfeng,Li, Haifeng,Du, Yijun,Cheng, Kai,Qi, Chenze
, p. 5030 - 5041 (2019/11/03)
A convenient method mediated by photoredox catalysis is developed for the direct construction of aryl alkynes. Readily available aromatic diazonium salts have been utilized as the aryl radical source to couple alkynyl carboxylic acids to feature the decarboxylative arylation. A wide range of substrates are amenable to this protocol with broad functional group tolerance, and diversely-functionalized aryl alkynes could be synthesized under mild, neutral and transition metal-free reaction conditions using visible light irradiation. Alongside synthetic sustainability associated with the photocatalytic and transition metal-free operation, another key point of this method is that the organic dye catalyst acts as an excited-state reductant, thus establishing the quenching cycle for radical addition and decarboxylative elimination. (Figure presented.).
NiCl2-catalyzed radical cross decarboxylative coupling between arylpropiolic acids and cyclic ethers
Wan, Zi-juan,Wang, Jin-yuan,Luo, Jun
supporting information, p. 613 - 616 (2019/01/29)
A direct alkenylation of cyclic ethers via radical cross decarboxylative coupling process catalyzed by NiCl2 and using DTBP as radical initiator and oxidant was developed. A variety of arylpropiolic acids and cyclic ethers were transformed into the corresponding 2-arylvinyl cyclic ethers in moderate to excellent yields. Mechanistic experiments were conducted to determine the nature of the reaction intermediates, and a plausible reaction mechanism involving NiCl2-promoted radical process was proposed.
Atom Transfer Oxidative Radical Cascade of Aryl Alkynoates towards 1,1-Dichalcogenide Olefins
Sahoo, Harekrishna,Ramakrishna, Isai,Mandal, Anup,Baidya, Mahiuddin
supporting information, p. 4549 - 4552 (2019/07/31)
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.
Visible-light-mediated selective thiocyanation/ipso-cyclization/oxidation cascade for the synthesis of thiocyanato-containing azaspirotrienediones
Chen, Yuan,Chen, Yu-Jue,Guan, Zhi,He, Yan-Hong
supporting information, (2019/11/26)
A visible-light-mediated metal-free thiocyanate radical addition/ipso-cyclization/oxidation cascade reaction for the synthesis of thiocyanato-containing azaspirotrienediones from N-phenylpropynamides is described. Cheap and readily available ammonium thiocyanate was used as a precursor to the thiocyanate free radical, which undergoes a radical addition reaction with the alkyne, followed by selective ipso-cyclization and oxidation to afford the dearomatized products. No product of ortho-cyclization was detected. The reaction completes the synthesis of C–S, C–C, and C[dbnd]O bonds in one pot, with abundant and renewable air oxygen as the sole sacrificial reagent and oxygen source.
Rhodium-catalyzed enantioselective decarboxylative alkynylation of allenes with arylpropiolic acids
Grugel, Christian P.,Breit, Bernhard
, p. 1066 - 1069 (2018/02/23)
A rhodium-catalyzed chemo-, regio-, and enantioselective intermolecular decarboxylative alkynylation of terminal allenes with arylpropiolic acids is reported. Employing a Rh(I)/(R)-Tol-BINAP catalytic system, branched allylic 1,4-enynes were obtained under mild conditions. The overall utility of this protocol is exemplified by a broad functional group compatibility.
Substrate-Assisted, Transition-Metal-Free Diboration of Alkynamides with Mixed Diboron: Regio- and Stereoselective Access to trans-1,2-Vinyldiboronates
Verma, Astha,Snead, Russell F.,Dai, Yumin,Slebodnick, Carla,Yang, Yinuo,Yu, Haizhu,Yao, Fu,Santos, Webster L.
supporting information, p. 5111 - 5115 (2017/04/24)
A substrate-assisted diboration of alkynamides using the unsymmetrical pinacolato-1,8-diaminonaphthalenato diboron (pinBBdan) is described. The transition-metal-free reaction proceeds in a regio- and stereoselective fashion to exclusively afford trans-vinyldiboronates in good to excellent yields. Notably, Bdan and Bpin are installed on the α- and β-carbon atoms, respectively.
