898288-14-7Relevant academic research and scientific papers
Facile and efficient enantioselective strecker reaction of ketimines by chiral sodium phosphate
Shen, Ke,Liu, Xiaohua,Cai, Yunfei,Lin, Lili,Feng, Xiaoming
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.
Enantioselective Strecker-type reaction of phosphinoyl ketimines catalyzed by a chiral Zr-bipyridyldiol catalyst
Chen, Yi-Jing,Chen, Chinpiao
experimental part, p. 2201 - 2209 (2009/04/05)
An enantioselective Strecker reaction of N-diphenylphosphinoyl ketimines with TMSCN employing a chiral zirconium complex formed from chiral bipyridyl diol 1 as catalyst is described. The catalytic efficiency of chiral ligand 1 with other Lewis acids was also explored. Higher yields (50-85%) with moderate to good enantioselectivities (30-80%) were achieved for a variety of N-diphenylphosphinoyl ketimines.
Enantioselective Strecker reaction of phosphinoyl ketoimines catalyzed by in situ prepared chiral N,N′-dioxides
Huang, Jinglun,Liu, Xiaohua,Wen, Yuehong,Qin, Bo,Feng, Xiaoming
, p. 204 - 208 (2007/10/03)
The enantioselective Strecker reaction of N-diphenylphosphinoyl ketoimines has been achieved by use of in situ prepared chiral N,N′-dioxide catalyst from L-piperidinamide 3f and m-chloroperoxybenzoic acid (m-CPBA). Excellent yields (up to 99%) and high enantioselectivities (up to 92% ee) were obtained. In particular, in situ prepared catalyst with readily available chiral material made the procedure more convenient. Moreover, the L-piperidinamide 3f-derived N,N′-dioxide 9 could be recycled and reused at least five times without any loss of either catalytic activity or enantioselectivity.
Assembly state of catalytic modules as chiral switches in asymmetric strecker amino acid synthesis
Kato, Nobuki,Mita, Tsuyoshi,Kanai, Motomu,Therrien, Bruno,Kawano, Masaki,Yamaguchi, Kentaro,Danjo, Hiroshi,Sei, Yoshihisa,Sato, Akihiro,Furusho, Sanae,Shibasaki, Masakatsu
, p. 6768 - 6769 (2007/10/03)
Self-assembled chiral polymetallic complexes often demonstrate novel properties as asymmetric catalysts. We report the three-dimensional structures of two such asymmetric catalysts (crystals A and B) for Strecker α,α-disubstituted amino acid synthesis. Th
Catalytic enantioselective Strecker reaction of ketoimines using catalytic amount of TMSCN and stoichiometric amount of HCN
Kato, Nobuki,Suzuki, Masato,Kanai, Motomu,Shibasaki, Masakatsu
, p. 3153 - 3155 (2007/10/03)
Catalyst loading as low as 0.1mol% was achieved in the enantioselective Strecker reaction of ketoimines. Excellent enantioselectivity was obtained with a combined use of a catalytic amount of TMSCN and a stoichiometric amount of HCN as a reagent, and a chiral gadolinium complex as a catalyst.
