61909-63-5Relevant academic research and scientific papers
Transition-Metal-Free Sulfuration/Annulation of Alkenes: Economical Access to Thiophenes Enabled by the Cleavage of Multiple C-H Bonds
Chen, Liang,Min, Hao,Zeng, Weilan,Zhu, Xiaoming,Liang, Yun,Deng, Guobo,Yang, Yuan
supporting information, p. 7392 - 7395 (2019/01/03)
A novel, atom economical, and transition-metal-free strategy for the synthesis of thiophenes from substituted buta-1-enes with potassium sulfide has been presented. The reaction achieves double C-S bond formations via cleavage of multiple C-H bonds and provides an efficient approach to access various functionalized thiophenes. Moreover, the strategy can also be used for the synthesis of thiophenes from 1,4-diaryl-1,3-dienes. Mechanistically, DMSO plays a role of oxidant and S3?- in situ generated from K2S is involved.
Chemoselective hydroamination of vinyl arenes catalyzed by an NHC-amidate-alkoxide Pd(II) complex and p-TsOH
Giles, Richard,O'Neill, Justin,Lee, Joo Ho,Chiu, Michael K.,Jung, Kyung Woon
, p. 4083 - 4085 (2013/07/25)
The hydroamination of various substituted vinyl arenes with benzenesulfonamide was explored using an NHC-amidate-alkoxide palladium catalyst in conjunction with p-TsOH. Utilizing halide-substituted and electron-rich vinyl arenes, this methodology selectively furnished the cross-coupled hydroamination products in moderate to excellent yields in a Markovnikov fashion while greatly reducing undesired acid-catalyzed homocoupling of the vinyl arenes. Electron-rich vinyl arenes typically required milder conditions than electron-poor ones. While most effective for para-substituted substrates, the catalyst system also furnished the desired products from ortho- and meta-substituted vinyl arenes with high chemoselectivities.
R-allyl nickel(II) complexes with chelating N-heterocyclic carbenes: Synthesis, structural characterization, and catalytic activity
Benitez Junquera, Lourdes,Puerta, M. Carmen,Valerga, Pedro
experimental part, p. 2175 - 2183 (2012/06/01)
The N-heterocyclic carbene (NHC) nickel complexes [(L)Ni(NHC)][BAr F4] (ArF = 3,5-bis(trifluoromethyl)phenyl; L = allyl (1), methylallyl (2); NHC = 1-(2-picolyl)-3-methylimidazol-2-ylidene (a), 1-(2-picolyl)-3-isopropylimidazol-2-ylidene (b), 1-(2-picolyl)-3-n- butylimidazol-2-ylidene (c), 1-(2-picolyl)-3-phenylimidazol-2-ylidene (d), 1-(2-picolyl)-3-methylbenzoimidazol-2-ylidene (e), 1-(2-picolyl)-4,5-dichloro-3- methylimidazol-2-ylidene (f)) have been obtained in high yields and characterized by NMR spectroscopy. Furthermore, 1d was unambiguously characterized by single-crystal X-ray crystallography. Complexes 1a-f/2a-f have shown catalytic activity toward dimerization and hydrosilylation of styrenes. In particular, 1a proved to be the most efficient catalyst in the dimerization of styrene derivatives in the absence of cocatalyst. Also, complexes 1a,d showed high selectivity and moderate to good yields in hydrosilylation reactions.
A new type of carbonylation of styrenes catalyzed by Pd(OAc)2 combined with molybdovanadophosphate
Yamada, Shingo,Obora, Yasushi,Sakaguchi, Satoshi,Ishii, Yasutaka
experimental part, p. 1194 - 1198 (2009/06/06)
A new type of carbonylation of styrenes was achieved under a 1:1 mixture of CO (0.5 atm) and O2 (0.5 atm) in the presence of Pd(OAc)2 combined with H5PMo10V2O40 nH 2O to give 4-methyl-2-phenylnaphthalen-1(4H)-one in 78% yield. Various substituted styrenes were also carbonylated to the corresponding substituted arylnaphthalen-l(4H)-ones in moderate yields. The reaction was found to proceed in two stages involving the head-to-tail dimerization of styrenes, followed by carbonylation of the resulting dimers. Styrenes were efficiently dimerized under air (1 atm) in the absence of CO even at room temperature to produce head-to-tail dimers in good yields.
