4436-93-5Relevant academic research and scientific papers
A one-pot two-step synthesis of tertiary alcohols combining the biocatalytic laccase/TEMPO oxidation system with organolithium reagents in aerobic aqueous media at room temperature
Capriati, Vito,Cicco, Luciana,García-álvarez, Joaquín,González-Sabín, Javier,Lecuna, Ramón,Presa Soto, Alejandro,Ríos-Lombardía, Nicolás,Ramos-Martín, Marina,Vitale, Paola
supporting information, p. 13534 - 13537 (2021/12/23)
The one-pot/two-step combination of enzymes and polar organometallic chemistry in aqueous media is for the first time presented as a proof-of-concept study. The unprecedented combination of the catalytic oxidation of secondary alcohols by the system laccase/TEMPO with the ultrafast addition (3 s reaction time) of polar organometallic reagents (RLi/RMgX) to thein situformed ketones, run under air at room temperature, allows the straightforward and chemoselective synthesis of tertiary alcohols with broad substrate scope and excellent conversions (up to 96%).
Combination of organocatalytic oxidation of alcohols and organolithium chemistry (RLi) in aqueous media, at room temperature and under aerobic conditions
Elorriaga, David,García-álvarez, Joaquín,González-Sabín, Javier,Hevia, Eva,Morís, Francisco,Presa Soto, Alejandro,Ríos-Lombardía, Nicolás,Rodríguez-álvarez, María Jesús
supporting information, p. 8932 - 8935 (2020/08/17)
A tandem protocol to access tertiary alcohols has been developed which combines the organocatalytic oxidation of secondary alcohols to ketones followed by their chemoselective addition by several RLi reagents. Reactions take place at room temperature, under air and in aqueous solutions, a trio of conditions that are typically forbidden in polar organometallic chemistry.
Synergistic Relay Reactions To Achieve Redox-Neutral α-Alkylations of Olefinic Alcohols with Ruthenium(II) Catalysis
Kan, Jian,Li, Chao-Jun,Li, Chen-Chen,Li, Jianbin,Lv, Leiyang,Qiu, Zihang
supporting information, p. 4544 - 4549 (2020/02/04)
Herein, we report a ruthenium-catalyzed redox-neutral α-alkylation of unsaturated alcohols based on a synergistic relay process involving olefin isomerization (chain walking) and umpolung hydrazone addition, which takes advantage of the interaction between the two rather inefficient individual reaction steps to enable an efficient overall process. This transformation shows the compatibility of hydrazone-type “carbanions” and active protons in a one-pot reaction, and at the same time achieves the first Grignard-type nucleophilic addition using olefinic alcohols as latent carbonyl groups, providing a higher yield of the corresponding secondary alcohol than the classical hydrazone addition to aldehydes does. A broad scope of unsaturated alcohols and hydrazones, including some complex structures, can be successfully employed in this reaction, which shows the versatility of this approach and its suitability as an alternative, efficient means for the generation of secondary and tertiary alcohols.
One-pot sustainable synthesis of tertiary alcohols by combining ruthenium-catalysed isomerisation of allylic alcohols and chemoselective addition of polar organometallic reagents in deep eutectic solvents
Cicco, Luciana,Rodríguez-álvarez, María J.,Perna, Filippo M.,García-álvarez, Joaquín,Capriati, Vito
supporting information, p. 3069 - 3077 (2017/07/24)
Ru(iv)-Catalysed redox isomerisation of allylic alcohols has, for the first time, been successfully assembled with the chemoselective addition of organolithium or organomagnesium reagents to the in situ formed ketones, en route to tertiary alcohols, employing deep eutectic solvents as environmentally friendly reaction media. The overall transformation, which formally involves three consecutive and different steps such as (i) the reduction of a C-C double bond, (ii) the oxidation of a secondary carbinol moiety, and (iii) a chemoselective C-C bond formation, takes place in protic and biorenewable eutectic mixtures in a sequential one-pot fashion using a commercially and easily available catalytic system, with excellent conversions (up to 99% yield), at room temperature and under air in the last step, with no concomitant reduction or enolisation processes, and with high atom economy, in agreement with the principles of the so-called green chemistry.
New ligands and structural insights into the catalytic asymmetric addition of organozinc reagents to ketones
Huelgas, Gabriela,Larochelle, Lynne K.,Rivas, Lucrecia,Luchinina, Yekaterina,Toscano, Rubén A.,Carroll, Patrick J.,Walsh, Patrick J.,Anaya De Parrodi, Cecilia
experimental part, p. 4467 - 4474 (2011/08/04)
The catalytic asymmetric addition of alkyl groups to ketones has received considerable attention. Outlined herein is the synthesis of two new ligands based on the C2-symmetric 11,12-diamino-9,10-dihydro-9,10- ethanoanthracene. The scope of the new ligands has been evaluated in the catalytic asymmetric addition of diethylzinc to a variety of ketones. Enantioselectivities as high as 99% have been achieved. The structures of two of these ligands have been determined by X-ray crystallography and are compared with related structures. Additionally, the structure of a titanium complex bound to a bis(sulfonamide) diol ligand is reported.
Efficient chemoselective addition of grignard reagents to carbonyl compounds in 2-methyltetrahydrofuran
Zhong, Weihui,Wu, Yaotiao,Zhang, Xingxian
experimental part, p. 370 - 373 (2009/12/25)
Compared with tetrahydrofuran (THF) as a solvent for the addition reactions between Grignard reagents and carbonyl compounds 2-methyltetrahydrofuran affords the corresponding adducts in higher yields with higher chemoselectivities. Moreover, 2-methyltetrahydrofuran can be readily recycled and reused, which lowers the cost of the process and makes the reaction greener.
Highly alkyl-selective addition to ketones with magnesium ate complexes derived from Gignard reagents
Hatano, Manabu,Matsumura, Tokihiko,Ishihara, Kazuaki
, p. 573 - 576 (2007/10/03)
(Chemical Equation Presented) A highly efficient alkyl-selective addition to ketones with magnesium ate complexes derived from Grignard reagents and alkyllithiums is described. The nucleophilicity of R in R3MgLi is remarkably increased compared to that of the original RLi or RMgX, while the basicity of R3MgLi is decreased. Furthermore, a highly R-selective addition to ketones is demonstrated using RMe2MgLi in place of R 3MgLi.
A Novel C-C Single-Bond Formation Accompanying C-O Bond Cleavage by Use of a Ketone, an Alkylating Reagent, and a Low-Valent Vanadium Complex in the Presence of a Catalytic Amount of Molecular Oxygen
Kataoka, Yasutaka,Akiyama, Hiroaki,Makihira, Isamu,Tani, Kazuhide
, p. 8109 - 8113 (2007/10/03)
A C-C single-bond-forming reaction from ketones with accompanying C-O bond cleavage mediated by a RMgBr or RLi-vanadium(II)-O2 system has been accomplished. Different from conventional reductive coupling reactions of ketones such as the McMurry coupling, the present method forms a C-C single (instead of a double) bond and yields a product that contains components derived from the ketone and the alkylating reagent in a one-pot reaction. Collaboration of both a low-valent vanadium(II) species and a higher-valent vanadium species produced from vanadium(II) and a catalytic amount of O2 effects the abstraction of the oxygen atom from a C-O bond.
Highly enantioselective addition of primary alkyl Grignard reagents to carbocyclic and heterocyclic arylketones in the presence of magnesium TADDOLate preparative and mechanistic aspects
Weber, Beat,Seebach, Dieter
, p. 6117 - 6128 (2007/10/02)
In the presence of equimolar amounts of the Mg alkoxide from α,α,α',α'-tetraphenyl-2,2-dimethyl-1,3-dioxolan-4,5-dimethanol (a TADDOL) primary Grignard reagents (Et, Pr, Bu, Oct, 3-butenyl) add to carbo- and heteroaromatic methyl ketones in THF at -100°C to give tertiary alcohols of enantiomeric excesses reaching values above 98%. The scope and limitation of the method are investigated. The reaction, which occurs in a vigorously stirred heterogeneous mixture, give best results in the absence of steric hindrance of the reacting centers; Grignard reagents made from alkyl bromides are superior to those obtained from chlorides; there is a perfect linear relationship between the ee of the TADDOL and of the product 2-phenyl-2-decanol; those tertiary alcohols of which the absolute configuration is known, are formed by nucleophilic attack from the Re face of the keto carbonyl groups. Three tentative mechanistic models for the stereochemical course of the reaction are discussed.
