57716-72-0Relevant academic research and scientific papers
Ir(NHC)-Catalyzed Synthesis of β-Alkylated Alcohols via Borrowing Hydrogen Strategy: Influence of Bimetallic Structure
Sung, Kihyuk,Lee, Mi-hyun,Cheong, Yeon-Joo,Kim, Yu Kwon,Yu, Sungju,Jang, Hye-Young
supporting information, p. 3090 - 3097 (2021/05/10)
Multi N-heterocyclic carbene(NHC)-modified iridium catalysts were employed in the β-alkylation of alcohols; dimerization of primary alcohols (Guerbet reaction), cross-coupling of secondary and primary alcohols, and intramolecular cyclization of alcohols. Mechanistic studies of Guerbet reaction, including kinetic experiments, mass analysis, and density functional theory (DFT) calculation, were employed to explain the fast reaction promoted by bimetallic catalysts, and the dramatic reactivity increase of monometallic catalysts at the late stage of the reaction. (Figure presented.).
C-C coupling formation using nitron complexes
Sevim, Mehmet,Kavukcu, Serdar Batikan,Kinal, Arma?an,?ahin, Onur,Türkmen, Hayati
supporting information, p. 16903 - 16915 (2020/12/18)
A series of RuII (1), RhIII (2), IrIII (3, 4), IrI (5) and PdII (6-9) complexes of the 'instant carbene' nitron were prepared and characterized by 1H- and 13C-NMR, FT-IR and elemental analysis. The molecular structures of complexes 1-4 and 6 were determined by X-ray diffraction studies. The catalytic activity of the complexes (1-9) was evaluated in alpha(α)-alkylation reactions of ketones with alcohol via the borrowing hydrogen strategy under mild conditions. These complexes were able to perform this catalytic transformation in a short time with low catalyst and base amounts under an air atmosphere. Also, the PdII-nitron complexes (6-9) were applied in the Suzuki-Miyaura C-C coupling reaction and these complexes successfully initiated this reaction in a short time (30 minutes) using the H2O/2-propanol (1.5?:?0.5) solvent system. The DFT calculations revealed that the Pd0/II/0 pathway was more preferable for the mechanism
Manganese-Catalyzed β-Alkylation of Secondary Alcohols with Primary Alcohols under Phosphine-Free Conditions
Liu, Tingting,Wang, Liandi,Wu, Kaikai,Yu, Zhengkun
, p. 7201 - 7207 (2018/07/21)
Manganese(I) complexes bearing a pyridyl-supported pyrazolyl-imidazolyl ligand efficiently catalyzed the direct β-alkylation of secondary alcohols with primary alcohols under phosphine-free conditions. The β-alkylated secondary alcohols were obtained in moderate to good yields with water formed as the byproduct through a borrowing hydrogen pathway. β-Alkylation of cholesterols was also effectively achieved. The present protocol provides a concise atom-economical method for C-C bond formation from primary and secondary alcohols.
Sodium Bromide-Catalyzed Oxidation of Secondary Benzylic Alcohols Using Aqueous Hydrogen Peroxide as Terminal Oxidant
Komagawa, Hiromi,Maejima, Yukako,Nagano, Takashi
supporting information, p. 789 - 793 (2016/03/09)
A halide salt, hydroperoxide and AcOH catalyst system was applied to the oxidation of secondary benzylic alcohols. This simple system can be applied to a variety of secondary benzylic alcohols and scaled up for gram-scale preparation. High secondary benzylic alcohol selectivity of the present method is demonstrated in hydroxyketone synthesis. Based on several experimental results, a catalytic cycle for our oxidation is proposed.
Tandem application of C-C bond-forming reactions with reductive ozonolysis
Willand-Charnley, Rachel,Dussault, Patrick H.
, p. 42 - 47 (2013/03/29)
Several variants of reductive ozonolysis, defined here as the in situ generation of aldehydes or ketones during ozonolytic cleavage of alkenes, are demonstrated to work effectively in tandem with a number of C-C bond-forming reactions. For reactions involving basic nucleophiles (1,2- addition of Grignard reagents, Wittig or Horner-Emmons olefinations, and directed aldol reactions of lithium enolates), the one-pot process offers a rapid and high-yielding alternative to traditional two-step protocols.
Preparation of alkylmagnesium reagents from alkenes through hydroboration and boron-magnesium exchange
Reichle, Markus A.,Breit, Bernhard
supporting information; experimental part, p. 5730 - 5734 (2012/08/14)
Tolerant: Alkylmagnesium reagents can be synthesized from alkenes through a sequence of hydroboration and subsequent boron-magnesium exchange using a method that tolerates different functional groups (see scheme). The resulting alkylmagnesium reagents can be used in carbon-carbon bond forming reactions, such as alkylation reactions or transition-metal-catalyzed cross-coupling reactions. Copyright
Iridium phosphine abnormal N-heterocyclic carbene complexes in catalytic hydrogen transfer reactions
Gong, Xue,Zhang, Hong,Li, Xingwei
, p. 5596 - 5600 (2011/11/06)
Several iridium complexes bearing chelating abnormal N-heterocyclic carbenes (NHCs) are shown to be active catalysts for transfer hydrogenation of ketones or enones, dehydrative C-C coupling between primary and secondary alcohols, and dehydrogenation of benzyl alcohol to benzyl benzoate. In the transfer hydrogenation of acetophenone, abnormal NHC complexes give higher activity than a normal analogue. Dehydrative C-C coupling reactions between primary and secondary alcohols result in β-alkylation of the secondary alcohols, using primary alcohols as the apparent alkylating reagents, and such reactions proceed with high yield and selectivity. These catalytic processes are known to involve metal-mediated temporary borrowing of hydrogen from alcohols and subsequent delivery of the hydrogen to CC and /or CO bonds.
Design of ionic liquids as a medium for the Grignard reaction
Itoh, Toshiyuki,Kude, Keisuke,Hayase, Shuichi,Kawatsura, Motoi
, p. 7774 - 7777 (2008/03/11)
Design of novel phosphonium ionic liquids that are compatible with Grignard reagents have been investigated; several types of phosphonium salts that have an alkyl ether moiety have been synthesized and their capability evaluated as solvents for Grignard reagents. It has been established that even basic aliphatic Grignard reagent-mediated reactions are possible when methoxyethyl(tri-n-butyl)phosphonium bis(trifluoromethanesulfonyl)imide is used as the solvent.
t-Bu-Amphos-RhCl3·3H2O: A highly recyclable catalyst system for the cross-coupling of aldehydes and aryl- and alkenylboronic acids in aqueous solvents
Huang, Rongcai,Shaughnessy, Kevin H.
, p. 4484 - 4486 (2007/10/03)
The combination of t-Bu-Amphos and RhCl3·3H2O gave the first highly recyclable catalyst for the coupling of aryl- and vinylboronic acids with aldehydes in aqueous solvents. The Royal Society of Chemistry 2005.
Practical Method for the Rhodium-Catalyzed Addition of Aryl- and Alkenylboronic Acids to Aldehydes
Fuerstner, Alois,Krause, Helga
, p. 343 - 350 (2007/10/03)
The arylation or alkenylation of aldehydes will boronic acids is conveniently effected by a catalyst system comprising RhCl3 · 3 H2O (1 mol %), the sterically hindered imidazolium salt 2 (1 mol %), and a base. The N-heterocyclic carbene 6 derived from 2 is believed to be the actual ligand to the catalytically active rhodium species formed in situ. The method is compatible with various functional groups in both reaction partners and follows a non-chelation controlled pathway in additions to the Garner aldehyde 25.
