77136-32-4Relevant articles and documents
Palladium-Catalyzed Highly Regioselective Hydrocarboxylation of Alkynes with Carbon Dioxide
Chen, Pengquan,Cheng, Ruixiang,Jiang, Huanfeng,Lei, Ming,Lou, Hongming,Qi, Chaorong,Shi, Fuxing,Wang, Lu,Wu, Wanqing,Xiong, Wenfang,Zhu, Baiyao
, p. 7968 - 7978 (2020/08/21)
A Pd-catalyzed highly regioselective hydrocarboxylation of alkynes with carbon dioxide has been established. By the combination of Pd(PPh3)4 and 2,2′-bis(diphenylphosphino)-1,1′-binaphthalene (binap), a variety of functionalized alkynes, including aryl alkynes, aliphatic alkynes, propargylamines, and propargyl ethers, could be leveraged to provide a wide array of α-acrylic acids in high yields with high regioselectivity under mild reaction conditions. Experimental and DFT mechanistic studies revealed that this reaction proceeded via the cyclopalladation process of alkynes and carbon dioxide in the presence of binap to generate a five-membered palladalactone intermediate and enabled the formation of Markovnikov adducts. Moreover, this strategy provided an effective method for the late-stage functionalization of alkyne-containing complicated molecules, including natural products and pharmaceuticals.
Copper-catalyzed hydrocarboxylation of alkynes using carbon dioxide and hydrosilanes
Fujihara, Tetsuaki,Xu, Tinghua,Semba, Kazuhiko,Terao, Jun,Tsuji, Yasushi
supporting information; experimental part, p. 523 - 527 (2011/03/16)
Getting a fix: The copper-catalyzed hydrocarboxylation of alkynes using carbon dioxide in the presence of a hydrosilane, which serves as a reducing agent, has been developed (see scheme). Copper fluorides bearing N-heterocyclic carbene ligands such as IMes and Cl2IPr show high catalytic activities.
Reactions d'addition conjuguee d'organolithiens aux acides carboxyliques α, β-insatures
Mortier, Jacques,Vaultier, Michel,Plunian, Barbara,Sinbandhit, Sourisak
, p. 98 - 112 (2007/10/03)
In THF at -78 deg C, organolithium derivatives and unprotected α,β-unsaturated carboxylic acids give a conjugated addition reaction. Reactions of 1- and 2-napthoic acids with various organolithium derivatives and electrophiles are reported. Two X-ray studies show that the reaction occurs with a good diastereoselectivity: the dilithiated enolate formed as an intermediate adds the electrophile exclusively via the face opposite to that of the organolithium. A study of the 1H NMR spectra of the products obtained shows that these compounds adopt a preffered conformation in solution. The protonolysis of the intermediate enolate by trifluoroacetic acid in an inverted mode gives rise to the formation of 1,2-disubstituted dihydronapthalenes. With acyclic α,β-unsaturated carboxylic acids, the diastereoselectivity of the reaction is marginal. With secondary butyllithium, the protonolysis of the intermediate enolates gives a 1,4-addition and an average diastereoselectivity. Reaction of phenylpropiolic acid with butyllithium gives rise to the formation of a produst resulting from a trans addition to the triple bond; the organolithium derivative adds in α to the carboxylic group. - Key words: 1,4-addition reactions; carboxylic acids; organolithium derivatives.
