54963-91-6Relevant academic research and scientific papers
Fast Enantio- and Chemoselective Arylation of Ketones with Organoboronic Esters Enabled by Nickel/N-Heterocyclic Carbene Catalysis
Cai, Yuan,Ruan, Lin-Xin,Rahman, Abdul,Shi, Shi-Liang
supporting information, p. 5262 - 5267 (2021/01/29)
A general, efficient, highly enantio- and chemoselective N-heterocyclic carbene (NHC)/Ni-catalyzed addition of readily available and stable arylboronic esters to ketones is reported. This protocol provides unexpectedly fast access (usually 10 min) to various chiral tertiary alcohols with exceptionally broad substrate scope and excellent functional group tolerance (76 examples, up to 98 % ee). This process is orthogonal to other known Ni-mediated Suzuki–Miyaura couplings, as it tolerates aryl chlorides, fluorides, ethers, esters, amides, nitriles, and alkyl chlorides. The reaction is applied to late-stage modifications of various densely functionalized medicinally relevant molecules. Preliminary mechanistic studies suggest that a rare enantioselective η2-coordinating activation of ketone carbonyls is involved. This cross-coupling-like mechanism is expected to enable other challenging transformations of ketones.
Enantioconvergent Arylation of Racemic Secondary Alcohols to Chiral Tertiary Alcohols Enabled by Nickel/N-Heterocyclic Carbene Catalysis
Cai, Yuan,Shi, Shi-Liang
supporting information, p. 11963 - 11968 (2021/08/20)
The direct upgrading reaction of simple and readily available achiral alcohols via C-H functionalization is an ideal strategy to prepare value-added chiral higher alcohols. Herein, we disclose the first enantioconvergent upgrading reaction of simple racemic secondary alcohols to enantioenriched tertiary alcohols. An N-heterocyclic carbene (NHC)-nickel catalyst was leveraged to enable this highly efficient formal asymmetric alcohol α-C-H arylation via a dehydrogenation using phenyl triflate as a mild oxidant followed by asymmetric addition of arylboronic esters to the transient ketones. Mechanistic studies and control experiments were conducted to reveal the possible reasons for the exceptional control over chemo- and enantioselectivity.
Catalytic Enantioselective Arylation and Heteroarylation of Ketones with Organotitanium Reagents Generated In Situ
Matsuda, Atsushi,Ushimaru, Tomoya,Kobayashi, Yusuke,Harada, Toshiro
supporting information, p. 8605 - 8609 (2017/06/30)
A practical and useful, catalytic enantioselective method has been developed for the synthesis of tertiary diaryl and aryl heteroaryl carbinols starting from commercially available aromatic ketones and aryl or heteroaryl bromides. In this method, organotitanium reagents are generated in situ from the bromides by lithiation with nBuLi followed by transmetallation of the resulting organolithiums with ClTi(OiPr)3. Treatment of the ketones with the titanium reagents in the presence of (R)-3-(3,5-bistrifluoromehthylphenyl)-1,1′-bi-2-naphthol (BTFP-BINOL) affords the corresponding tertiary alcohols in high enantioselectivities and yields. The reaction can also start with furan and 2-thienyllithium. The method is operationally simple and can be conducted on a 10-mmol scale without any difficulties.
Chromium(II)-catalyzed enantioselective arylation of ketones
Wang, Gang,Sun, Shutao,Mao, Ying,Xie, Zhiyu,Liu, Lei
supporting information, p. 2771 - 2775 (2017/01/09)
The chromium-catalyzed enantioselective addition of carbo halides to carbonyl compounds is an important transformation in organic synthesis. However, the corresponding catalytic enantioselective arylation of ketones has not been reported to date. Herein, we report the first Cr-catalyzed enantioselective addition of aryl halides to both arylaliphatic and aliphatic ketones with high enantioselectivity in an intramolecular version, providing facile access to enantiopure tetrahydronaphthalen-1-ols and 2,3-dihydro-1H-inden-1-ols containing a tertiary alcohol.
Zn(salen)-catalyzed enantioselective phenyl transfer to aldehydes and ketones with organozinc reagent
Shimizu, Keisuke,Uetsu, Hidenori,Gotanda, Takashi,Ito, Katsuji
, p. 1238 - 1242 (2015/03/31)
Abstract A chiral zinc complex of salen was found to be an efficient catalyst for the phenyl transfer of organozinc reagent to aromatic aldehydes and ketones. High enantioselectivities were obtained in reactions of both aromatic aldehydes and ketones (up to 97% and 92% ee, respectively).
Catalytic Enantioselective Addition of Aryl Grignard Reagents to Ketones
Fernández-Mateos, Emilio,Maciá, Beatriz,Yus, Miguel
, p. 6519 - 6526 (2016/02/18)
We report a catalytic system for the challenging enantioselective addition of aryl Grignard reagents to ketones. Using a simple, one-pot procedure under mild conditions, a wide range of aromatic ketones are converted into diaryl alcohols in good yields and with good enantioselectivities. The catalytic enantioselective addition of aryl Grignard reagents to ketones is now possible. Using a readily available Ar-BINMOL ligand and titanium(IV) isopropoxide in a simple, one-pot procedure under mild conditions, a wide range of aromatic ketones are converted into diaryl alcohols in good yields and with good enantioselectivities.
Rhodium(I)/diene-catalyzed addition reactions of arylborons with ketones
Liao, Yuan-Xi,Xing, Chun-Hui,Hu, Qiao-Sheng
supporting information; experimental part, p. 1544 - 1547 (2012/06/05)
Rh(I)/diene-catalyzed addition reactions of arylboroxines/arylboronic acids with unactivated ketones to form tertiary alcohols in good to excellent yields are described. By using C2-symmetric (3aR,6aR)-3,6-diaryl-1,3a,4,6a- tetrahydropentalenes as ligands, the asymmetric version of such an addition reaction, with up to 68% ee, was also realized.
Commercially available neat organozincs as highly reactive reagents for catalytic enantioselective addition to ketones and aldehydes under solvent free conditions
Hatano, Manabu,Mizuno, Tomokazu,Ishihara, Kazuaki
experimental part, p. 4417 - 4424 (2011/08/06)
Neat Et2Zn, Ph2Zn, and highly concentrated Me 2Zn are highly reactive organozinc reagents, which are commercially available in bulk quantities. We here report a catalytic enantioselective Et2Zn, Ph2Zn, and Me2Zn addition to ketones and aldehydes under solvent free or highly concentrated conditions without Ti(Oi-Pr)4 as a conventional activator of organozinc reagents. The desired optically active tertiary and secondary alcohols were obtained in good yield with high enantioselectivity when compared to the conventional solvent-use conditions. From the viewpoint of ecological and environmental reasons in green chemistry, this catalysis would be practical for not only academic but also industrial use.
Highly active chiral phosphoramide-Zn(II) complexes as conjugate acid-base catalysts for enantioselective organozinc addition to ketones
Hatano, Manabu,Miyamoto, Takashi,Ishihara, Kazuaki
, p. 4535 - 4538 (2008/03/12)
(Chemical Equation Presented) A highly efficient enantioselective organozinc (R2Zn) addition to ketones catalyzed by chiral phosphoramide-Zn(II) complexes (1-10 mol %) has been developed. These complexes serve as conjugate Lewis acid-Lewis base
