185144-38-1Relevant articles and documents
Novel non-metal catalyst for catalyzing asymmetric hydrogenation of ketone and alpha, beta-unsaturated ketone
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Paragraph 0174-0179, (2021/04/26)
The invention discloses a novel non-metal catalyst for catalyzing asymmetric hydrogenation of ketone and alpha, beta-unsaturated ketone. The preparation method of a chiral alcohol compound shown as formula IV comprises the following step of: reacting a ketone compound shown as formula V with hydrogen under the catalysis of tri(4-hydrotetrafluorophenyl)boron and a chiral oxazoline compound to obtain the chiral alcohol compound shown as the formula IV; the preparation method of a chiral tetralone compound shown as formula VI comprises the following step of: under the catalysis of tri(4-hydrotetrafluorophenyl)boron and a chiral oxazoline compound, reacting an alpha, beta-unsaturated ketone compound shown as formula VII with hydrogen to obtain the chiral tetralone compound shown as the formula VI. The method has the advantages of easy synthesis of raw materials, mild reaction conditions, simple operation, high stereoselectivity and the like, the ee value of the product is up to 92%, and the yield is up to 99%.
Asymmetric Hydrogenation of Ketones and Enones with Chiral Lewis Base Derived Frustrated Lewis Pairs
Du, Haifeng,Feng, Xiangqing,Gao, Bochao,Meng, Wei
supporting information, p. 4498 - 4504 (2020/02/05)
The concept of frustrated Lewis pairs (FLPs) has been widely applied in various research areas, and metal-free hydrogenation undoubtedly belongs to the most significant and successful ones. In the past decade, great efforts have been devoted to the synthesis of chiral boron Lewis acids. In a sharp contrast, chiral Lewis base derived FLPs have rarely been disclosed for the asymmetric hydrogenation. In this work, a novel type of chiral FLP was developed by simple combination of chiral oxazoline Lewis bases with achiral boron Lewis acids, thus providing a promising new direction for the development of chiral FLPs in the future. These chiral FLPs proved to be highly effective for the asymmetric hydrogenation of ketones, enones, and chromones, giving the corresponding products in high yields with up to 95 % ee. Mechanistic studies suggest that the hydrogen transfer to simple ketones likely proceeds in a concerted manner.
Advantageous asymmetric ketone reduction with a competitive hydrogenation/transfer hydrogenation system using chiral bifunctional iridium catalysts
Moritani, Junki,Kayaki, Yoshihito,Ikariya, Takao
, p. 61001 - 61004 (2015/02/19)
Hydrogenation of aromatic ketones with chiral bifunctional amidoiridium complexes proceeds in preference to transfer hydrogenation in methanol, in which the pressurised hydrogen can suppress unintended racemisation of the alcoholic product, leading to enh
Catalytic enantioselective addition of organoaluminum reagents to aldehydes
Fernandez-Mateos, Emilio,MacIa, Beatriz,Yus, Miguel
experimental part, p. 789 - 794 (2012/09/05)
An efficient catalyst for the asymmetric addition of organoaluminum reagents to aldehydes is presented. The system is based on a readily available binaphthyl derivative as a chiral ligand and an excess of titanium tetraisopropoxide. The asymmetric methylation, ethylation, and propylation of a wide variety of aromatic and aliphatic aldehydes proceeded with good yields and with high enantioselectivities in a simple one-pot procedure under mild conditions.
Enantioselective addition of methyl group to aldehydes catalyzed by titanium complex of fluorous ligand
Omote, Masaaki,Tanaka, Naoya,Tarui, Atsushi,Sato, Kazuyuki,Kumadaki, Itsumaro,Ando, Akira
, p. 2989 - 2991 (2008/02/04)
Titanium complex of fluorous axially dissymmetric ligand ((Ra*)-2,2′-bis[(R*)-perfluoro-1H-1-hydroxyoctyl]biphenyl, ((Ra*)-(R*)2-1)) having perfluoroheptyl carbinol moieties catalyzed enantioselective addition of a methyl group to aldehydes. Dimethylzinc prepared in situ by mixing ZnCl2 and methyl magnesium bromide without removal of magnesium salt was more reactive for addition of methyl group than dimethylzinc without magnesium salt, and gave up to 99% ee of the products. The high fluorine content of 1 enables it to be recoverable by the selective extraction with perfluorohexane.
Photo-Arbuzov rearrangements of 1-arylethyl phosphites: Stereochemical studies and the question of radical-pair intermediates
Bhanthumnavin,Bentrude
, p. 980 - 990 (2007/10/03)
The direct UV irradiation of the 1-arylethyl phosphites 7, 8, and 9 was carried out in acetonitrile, benzene, and cyclohexane, as was the triphenylene-sensitized reaction of 9. Dimethyl 1-phenylethyl phosphite, 7, gives the photo-Arbuzov rearrangement pro
Highly enantioselective reduction of symmetrical diacetylaromatics with baker's yeast
Uchiyama, Masahiko,Katoh, Nobuo,Mimura, Rio,Yokota, Naoko,Shimogaichi, Yuki,Shimazaki, Makoto,Ohta, Akihiro
, p. 3467 - 3474 (2007/10/03)
Asymmetric reduction of symmetrical diacetylaromatics (1a, 1b, and 1d- g) with baker's yeast (Saccharomyces cerevisiae) provided the corresponding alcohols of high enantiomeric purity. By choosing appropriate reaction conditions, the products were preferentially the monoalcohols over the diols.
An efficient preparation of optically pure C2-symmetric aromatic diols by the asymmetric reduction of diacylaromatic compounds with B- chlorodiisopinocampheylborane
Ramachandran,Chen,Lu,Brown
, p. 3795 - 3798 (2007/10/03)
Asymmetric reduction of diacylaromatic compounds with B- chlorodiisopinocampheylborane provides the product diols in excellent diastereomeric and enantiomeric purity.
Differentiation and assigment of the proton NMR signals in the bis-MTPA ester of meso-α,α'-dimethyl-1,4-benzenedimethanol
Baldwin, Bruce W.,Morrow, Cary J.
, p. 2871 - 2878 (2007/10/03)
NaBH4 reduction of one ketone in 1,4-diacetylbenzene followed by Amano PS catalyzed acylation of the R enantiomer, separation of the R acetate from the S alcohol, and reduction of the remaining ketone in each with NaBD4, has provided
