57438-46-7Relevant academic research and scientific papers
Efficient, selective, and green: Catalyst tuning for highly enatioselective reactions of ethylene
Smith, Craig R.,Rajanbabu
supporting information; experimental part, p. 1657 - 1659 (2009/04/10)
Fine tuning of the biaryl and amino moieties of Feringa's phosphoramidite ligands yields structurally simpler, yet more efficient and selective, ligands for asymmetric hydrovinylation of vinylarenes and acylic 1,3-dienes. The enantioselectivities and yields observed in the formation of the 3-arylbutenes are among the highest for all asymmetric catalytic processes reported to date for the synthesis of intermediates for the widely used antiinflammatory 2-arylpropionic acids including naproxen, ibuprofen, fenoprofen, and flurbiprofen.
γ-selective cross-coupling of potassium allyltrifluoroborates with aryl and 1-alkenyl bromides catalyzed by a Pd(OAc)2/D-t-BPF complex
Yamamoto, Yasunori,Takada, Shingo,Miyaura, Norio
, p. 704 - 705 (2007/10/03)
Cross-coupling reactions of [RCH=CHCH2BF3]K with aryl or 1-alkenyl bromides occurred at the γ-carbon of an allylborane moiety with perfect regioselectivities (>99%) in the presence of a palladium/D-t-BPF complex and K2COs
Heterodimerization of Olefins. 1. Hydrovinylation Reactions of Olefins That Are Amenable to Asymmetric Catalysis
RajanBabu,Nomura, Nobuyoshi,Jin, Jian,Nandi, Malay,Park, Haengsoon,Sun, Xiufeng
, p. 8431 - 8446 (2007/10/03)
Through a systematic examination of ligand and counterion effects, new protocols for a nearly quantitative and highly selective codimerization of ethylene and various functionalized vinylarenes have been discovered. In a typical reaction, 4-bromostyrene and ethylene undergo codimerization in the presence of 0.0035 equiv each of [(allyl)NiBr]2, triphenylphosphine, and AgOTf in CH2Cl2 at -56 °C to give 3-(4-bromophenyl) -1-butene in >98% yield and selectivity. Corresponding reactions with [(allyl)PdX]2 are much less efficient and less selective and may require further optimization before a viable system can be identified. Another useful protocol that gives comparable yield and selectivity involves the use of a single-component catalyst prepared from allyl 2-diphenylphosphinobenzoate, Ni(COD)2, and (C6F5)3B. Recognition of a synergistic relationship between a chiral hemilabile ligand (for example, (R)-2-methoxy-2′-diphenylphosphino-1,1′-binaphthyl, MOP) and a highly dissociated counteranion (BARF or SbF6) in an enantioselective version of the Ni-catalyzed reaction raises the prospects of developing a practical route for the synthesis of 3-arylbutenes. Several pharmaceutically relevant compounds, including widely used 2-arylpropionic acids, can be synthesized from these key intermediates. This reaction appears to be quite general. Synthesis of several new 2-diphenylphosphino-1,1-binaphthyl derivatives, prepared to probe the effect of hemilabile coordination on the efficiency and selectivity of the reaction, are also described.
Heterodimerization of propylene and vinylarenes: Functional group compatibility in a highly efficient Ni-catalyzed carbon-carbon bond-forming reaction
Jin, Jian,Rajanbabu
, p. 2145 - 2151 (2007/10/03)
Unlike heterodimerization reactions of ethylene and vinylarenes, no such synthetically useful reactions using propylene are known. We find that propylene reacts with various vinylarenes in the presence of catalytic amounts of [(allyl)NiBr]2, tr
Nickel catalyzed hydrovinylation of arylethylenes: General method of synthesis of α-arylpropionic acids intermediates
Fassina, Viviane,Ramminger, Carolina,Seferin, Marcus,Monteiro, Adriano L
, p. 7403 - 7409 (2007/10/03)
The hydrovinylation of arylethylenes catalyzed by [Ni(MeCN)6][BF4]2/AlEt2Cl/PPh3 was modulated to obtain 3-aryl-1-butenes in high yields and selectivities. A wide variety of arylethylenes containing electron-donating or electron-withdrawing groups and Lewis basic group, can be hydrovinylated at room temperature and under mild conditions by changing the relative ratios of the three-component catalyst. Similar activities and selectivities were observed for o-, m- and p-substituted styrenes. Also, the hydrovinylation of olefins with substituents in the vinyl fragment, such as α-methylstyrene and indene, can be accomplished. (C) 2000 Elsevier Science Ltd.
