124475-73-6Relevant academic research and scientific papers
Regio- and Stereoselective Synthesis of 2-Hydroxymethyl-1,3-enynes by Rhodium-Catalyzed Decarboxylative C?C Coupling
Lu, Shi-Chao,Chang, Zhi-Xin,Xiao, Yu-Liang,Li, Hong-Shuang
, p. 4831 - 4836 (2019)
A regio- and stereoselective protocol for rhodium(I)-catalyzed decarboxylative C?C coupling between propiolic acids and propargyl alcohols has been achieved. This efficient catalytic approach could facilitate the preparation of a diversity of synthetically valuable 2-hydroxymethyl-1,3-enynes with high Z-stereoselectivity. Notably, non-terminal alkynes were smoothly transformed into the target products that show intriguing synthetic utility. (Figure presented.).
Cobalt-Catalyzed gem-Cross-Dimerization of Terminal Alkynes
Chen, Jia-Feng,Li, Changkun
, p. 3881 - 3889 (2020/03/26)
Transition-metal-catalyzed dimerization of two different terminal alkynes provides an atom-economic synthesis of valuable conjugated 1,3-enynes. Despite many catalyst systems developed, the state-of-the-art solutions are still limited to special alkynes. A practical catalyst, which could be used to cross-dimerize general aryl alkynes and aliphatic alkynes, is still highly desired. Herein we present the earth-abundant Co(II)-catalyzed highly gem-selective cross-dimerization of aryl alkynes and aliphatic alkynes or gas acetylene under mild reaction conditions. Conjugated 1,3-enynes with various useful functional groups can be prepared in high yields. The application of Co(OAc)2 and t-butyl group substituted triphos ligand is essential to distinguish the alkynes at different steps and realize the gem-selectivity.
Catalytic cascade hydroalkoxylation/isomerization/[4 + 2] cycloaddition using enyne alcohols as latent dienes or dienophiles
Guo, Rui,Li, Kang-Nan,Gong, Liu-Zhu
supporting information, p. 6707 - 6712 (2013/10/01)
Enyne alcohols can react as precursors of either dienes or dienophiles with different substrates after hydroxylation and isomerization by gold catalysis. As such, oxa-bridged tricyclo[5.2.2.02,6]undec-8-ene-3,5-dione derivatives have been obtained by the Diels-Alder reaction and tetrahydro-1H-furo[3,4-c]pyran derivatives could be accessed by the hetero-Diels-Alder cycloaddition.
First direct synthesis of 3-hydroxy-pent-4-ynoic acids. Application to the synthesis of pyran-2-ones
López-Reyes, Morelia E.,López-Cortés, José G.,Ortega-Alfaro, M. Carmen,Toscano, R. Alfredo,Alvarez-Toledano, Cecilio
, p. 7365 - 7372 (2013/08/23)
We describe a direct method for the synthesis of 3-hydroxy-pent-4-ynoic acids by the nucleophilic addition of bis-(TMS) ketene acetals to alkynones promoted by BF3·Et2O. A systematic study involving electron withdrawing and electron donor groups (R1=NO2, CF3, Br, Cl, H, Me, OMe) in the propargyl ketone reveals a strong dependence of electronic effects on the regiochemistry of the nucleophilic addition. Using a halolactonization protocol, we demonstrated the synthetic potential of these acids by their efficient transformation into new 5-bromo-3,4-dihydro-2H-pyran-2-ones.
Cyclization cascades initiated by 1,6-conjugate addition
Brooks, Joshua L.,Frontier, Alison J.
supporting information, p. 16551 - 16553,3 (2020/09/15)
Dienyl diketones containing tethered acetates selectively undergo two different 1,6-conjugate addition-initiated cyclization cascades. One is a 1,6-conjugate addition/cyclization sequence with incorporation of the nucleophile, and the other is catalyzed by DABCO and is thought to proceed via a cyclic acetoxonium intermediate. The reaction behavior of substrates lacking the tethered acetate was also studied. The scope of both types of cyclization cascades, the role of the amine additive, and the factors controlling reactivity and selectivity in the two different reaction pathways is discussed.
A NEW PALLADIUM CATALYST, METHOD FOR ITS PREPARATION AND ITS USE
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Page/Page column 26, (2012/07/27)
The invention relates to palladium(0)-tetrakis{tri-[3,5-bis(trifluoromethyl)- phenylj-phosphine} complex of formula (I), as well as to its preparation and use. This compound is outstandingly stable, and can be used as catalyst with excellent results.
A simple microwave-assisted preparation of 2-bromo-1-alkenes from 1-alkynes using the LiBr-TMSCl-TEAB reagent system
Bunrit, Anon,Ruchirawat, Somsak,Thongsornkleeb, Charnsak
scheme or table, p. 3124 - 3127 (2011/06/26)
2-Bromo-1-alkenes are cleanly and conveniently generated in good yields and selectivities via microwave-assisted hydrobromination of 1-alkynes using a combination of lithium bromide (LiBr), chlorotrimethylsilane (TMSCl), and tetraethylammonium bromide (TEAB) in acetonitrile (MeCN).
Lewis acid catalyzed propargylation of arenes with O-propargyl trichloroacetimidates: Synthesis of 1,3-diarylpropynes
Li, Changkun,Wang, Jianbo
, p. 7431 - 7434 (2008/02/11)
(Chemical Equation Presented) The BF3·OEt 2-catalyzed Friedel-Crafts propargylation of aromatic compounds with O-propargyl trichloroacetimidates is highly efficient and affords 1,3-diarylpropyne derivatives in good yields.
Efficient synthesis of enynes by tetraphosphine-palladium-catalysed reaction of vinyl bromides with terminal alkynes
Feuerstein, Marie,Chahen, Ludovic,Doucet, Henri,Santelli, Maurice
, p. 112 - 120 (2007/10/03)
Through the use of [PdCl(C3H5)]2/cis,cis, cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane as catalyst, a range of vinyl bromides undergoes Sonogashira cross-coupling reaction with a variety of alkynes, leading to
A simple catalyst system for the palladium-catalyzed coupling of aryl halides with terminal alkynes
Shirakawa, Eiji,Kitabata, Takaaki,Otsuka, Hidehito,Tsuchimoto, Teruhisa
, p. 9878 - 9885 (2007/10/03)
A convenient catalyst system consisting of Pd(OAc)2, PPh 3, K3PO4 and DMSO was found to be effective for the coupling reaction of aryl halides with terminal alkynes as well as the deacetonative coupling reaction using a 4-aryl-2-methylbut-3-yn-2-ol as a terminal alkyne precursor. An iminophosphine as a ligand worked more effectively for some combination of substrates than triphenylphosphine.
