699006-54-7Relevant academic research and scientific papers
Direct Asymmetric Friedel-Crafts Reaction of Naphthols with Acetals Catalyzed by Chiral Bronsted Acids
Qin, Long,Wang, Pei,Zhang, Yixin,Ren, Zhengxiang,Zhang, Xin,Da, Chao-Shan
, p. 571 - 574 (2016/03/01)
The Friedel-Crafts method synthesis of chiral ethers from various acetals and naphthols catalyzed by chiral Bronsted acids with acetic acid as an effective additive is described. We found that the chiral phosphoric acid (R)-TRIP could efficiently catalyze the asymmetric Friedel-Crafts reaction of naphthols with acetals affording chiral ethers in good enantioselectivity and yield.
Synthesis of novel chiral phosphoric acid-bearing two acidic phenolic hydroxyl groups and its catalytic evaluation for enantioselective Friedel-Crafts alkylation of indoles and enones
Liu, Xiong-Li,Yu, Zhang-Biao,Pan, Bo-Wen,Chen, Lin,Feng, Ting-Ting,Zhou, Ying
, p. 628 - 634 (2015/03/30)
A novel chiral phosphoric acid catalyst bearing two acidic phenolic hydroxyl groups was synthesized. Its catalytic activity as a chiral Br?sted acid has been examined in the enantioselective Friedel-Crafts alkylation of indoles and enones as a model reaction. In comparison with the other chiral phosphoric acid catalysts, the reaction catalyzed by the novel chiral catalyst afforded the desired 3-substituted indoles in a higher enantioselectivity (up to 69% ee).
Organocatalytic asymmetric synthesis of propargylamines with two adjacent stereocenters: Mannich-type reactions of in situ generated C-alkynyl imines with β-keto esters
Kano, Taichi,Yurino, Taiga,Maruoka, Keiji
supporting information, p. 11509 - 11512 (2013/11/06)
Side by side: The title reaction is catalyzed by the chiral Bronsted acid (S)-1, and affords hitherto less accessible chiral propargylamines, having two adjacent stereocenters, in good to excellent diastereo- and enantioselectivities. Boc=tert-butoxycarbonyl. Copyright
Chiral phosphoric acid catalyzed asymmetric friedel-crafts alkylation of indoles with nitroolefins
Tang, Hong-Ying,Zhang, Zhong-Biao
, p. 2038 - 2046 (2011/11/30)
Asymmetric Michael-type Friedel-Crafts (F-C) alkylations of indoles with nitroolefins catalyzed by a chiral H8-BINOL-based phosphoric acid were investigated. The reactions took place very smoothly in the presence of only 5 mol-% of catalyst at
Facile and efficient enantioselective strecker reaction of ketimines by chiral sodium phosphate
Shen, Ke,Liu, Xiaohua,Cai, Yunfei,Lin, Lili,Feng, Xiaoming
supporting information; scheme or table, p. 6008 - 6014 (2010/02/28)
A facile and efficient enantioselective Strecker reaction of ketimines catalyzed by a chiral alkali-metal salt has been developed. When 10 mol% BNPNa (BNP=1,1'-binaphthyl-2,2'-diylphosphate) prepared in situ and 10 mol% para-tert-butylortho-adamantylphenol (PBAP) were introduced into the reaction, up to 96% yield and up to 95% ee (ee=enantiomeric excess) were obtained. Both aliphatic and aromatic ketimines, especially sterically bulky cyclic ketimines derived from β-acetonaphthone, α-indanone, and α-tetralone were found suitable for this reaction. On the basis of the experimental results and previous reports, trimethylsilyl cyanide (TMSCN) was indicated to be the real reactive nucleophile despite the existence of PBAP, and a possible working model was proposed to explain the origin of the asymmetric induction. The facile availability of 1,1'-binaphthyl-2,2'-diylphosphoric acid (BNPH) and the simplicity of the procedure are beneficial for practical applications.
Chiral phosphoric acid catalyzed asymmetric Friedel-Crafts alkylation of indoles with simple α,β-unsaturated aromatic ketones
Tang, Hong-Ying,Lu, Ai-Dang,Zhou, Zheng-Hong,Zhao, Guo-Feng,He, Lian-Nian,Tang, Chu-Chi
experimental part, p. 1406 - 1410 (2009/04/04)
Asymmetric Michael-type Friedel-Crafts (F-C) alkylations of indoles with nonchelating α,β-unsaturated aromatic ketones catalyzed by a chiral H8-BINOL-based phosphoric acid were investigated. The reactions took place smoothly in the presence of
Chiral lithium salts of phosphoric acids as Lewis acid-base conjugate catalysts for the enantioselective cyanosilylation of ketones
Hatano, Manabu,Ikeno, Takumi,Matsumura, Tokihiko,Torii, Shinobu,Ishihara, Kazuaki
supporting information; experimental part, p. 1776 - 1780 (2009/07/01)
The catalytic enantioselective cyanosilylation of aromatic ketones was developed by using chiral lithium salts of (R)-BINOL- or (S)-BINAM-derived phosphoric acid compounds. In the presence of 10 mol% of chiral conjugate lithium salts, the corresponding tertiary cyanohydrins were obtained in high yields with moderate to high enantio-selectivities. This is the first efficient example of asymmetric catalysis using lithium salts of synthetically useful chiral phosphoric acid compounds. A possible catalytic mechanism and transition states are also discussed as a preliminary working hypothesis.
ASYMMETRIC-SYNTHESIS CATALYST BASED ON CHIRAL BROENSTED ACID AND METHOD OF ASYMMETRIC SYNTHESIS WITH THE CATALYST
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Page/Page column 18, (2010/11/08)
A compound usable as an asymmetric synthesis catalyst which can be easily synthesized without using any metal such as a lanthanoid group element; a method of asymmetric synthesis with the compound; and a chiral compound obtained by the asymmetric synthesis method. A Broensted acid is used as a catalyst in asymmetric synthesis, the chiral Broensted acid being represented by formula (1) below or formula (3) below. The asymmetric synthesis method employs the catalyst. Asymmetric synthesis with the catalyst gives a chiral compound.
