395-10-8Relevant academic research and scientific papers
Rhodium-Catalyzed meta-Selective C?H Carboxylation Reaction of 1,1-Diarylethylenes via Hydrorhodation-Rhodium Migration
Caner, Joaquim,Iwasawa, Nobuharu,Saito, Takanobu,Toriumi, Naoyuki
supporting information, p. 23349 - 23356 (2021/09/18)
A meta-selective C?H carboxylation reaction of 1,1-diarylethylene derivatives with CO2 by using a rhodium catalyst with NaOiPr as a stoichiometric reductant has been achieved. Together with hydrogenation of the ethylene moiety, a carboxyl group was introduced to the meta-position of the aryl ring with high selectivity over the ortho-positions. Experimental and computational mechanistic studies indicate that this carboxylation reaction proceeds via hydrorhodation on the ethylene moiety, followed by 1,4-rhodium migration and successive 1,2-rhodium migration on the aryl ring. The use of a bulky phosphine ligand seems to be the key to this unusual aryl-to-aryl 1,2-rhodium shift.
Base-promoted addition of DMA with 1,1-diarylethylenes: Application to a total synthesis of (-)-sacidumlignan B
Luo, Zhen-Biao,Peng, Yu,Wang, Ya-Wen
supporting information, p. 2054 - 2057 (2020/03/27)
A base-promoted addition of DMA (N,N-dimethylacetamide) to 1,1-diarylethylenes has been developed, and it provides a new strategy for the synthesis of N,N-dimethyl-4,4-diarylbutanamides from 1,1-diarylethylenes at room temperature. This method allows us to achieve the goal of synthesizing (-)-sacidumlignan B, and provides simple operation and broad substrate scope by avoiding the use of transition metal catalysts.
Br?nsted Acid Catalyzed Peterson Olefinations
Britten, Thomas K.,McLaughlin, Mark G.
, p. 301 - 305 (2019/12/25)
A mild and facile Peterson olefination has been developed employing low catalyst loading of the Br?nsted acid HNTf2. The reactions are typically performed at room temperature, with the reaction tolerant to a range of useful functionalities. Furthermore, we have extended this methodology to the synthesis of enynes.
Selective arylation and vinylation at the α position of vinylarenes
Zou, Yinjun,Qin, Liena,Ren, Xinfeng,Lu, Yunpeng,Li, Yongxin,Zhou, Jianrong
supporting information, p. 3504 - 3511 (2013/07/05)
In intermolecular Heck reactions of styrene and vinylarenes, the aryl and vinyl groups routinely insert at the β position. However, selective insertion at the α position has been very rare. Herein, we provide a missing piece in the palette of Heck reaction, which gave >20:1 α selectivity. The key to our success is a new ferrocene 1,1′-bisphosphane (dnpf) that carries 1-naphthyl groups. Our mechanistic studies revealed that the high α selectivity is partly attributable to the steric effect of dnpf. The rigid and bulky 1-naphthyl groups of dnpf sterically disfavor β insertion. What the Heck! In intermolecular Heck reactions, insertion at the β position of aromatic olefins is very common, but reversal of the selectivity for selective α insertion has been a longstanding problem. A general method to couple aryl and vinyl triflates with aromatic olefins in >20:1 α selectivity is presented. The key to this successful approach is a new ferrocene bisphosphane with naphthyl groups on the phosphorus atom (see scheme; OTf=triflate). Copyright
Synthesis of benzophenones from geminal biaryl ethenes using m-chloroperbenzoic acid
Singh, Fateh V.,Milagre, Humberto M.S.,Eberlin, Marcos N.,Stefani, Helio A.
experimental part, p. 2312 - 2316 (2009/09/06)
The oxidation of geminal biaryl ethenes 3 and 1,3-enynes 5 using m-chloroperbenzoic acid in dichloromethane at room temperature presents a catalyst-free approach for the synthesis of functionalized benzophenones 4 and ynones 6, respectively.
