170379-92-7Relevant academic research and scientific papers
Design of a Chiral Ionic Liquid System for the Enantioselective Addition of Diethylzinc to Aldehydes
Ferrari Bach, Mariana,Herzer Griebeler, Cassiana,Gross Jacoby, Caroline,Schneider, Paulo Henrique
supporting information, p. 6997 - 7004 (2017/12/26)
An important contribution to the field of asymmetric catalysis is described in this work, as it merges the search for new ligands that can provide high performance in asymmetric catalysis with the extremely important and increasing need for sustainability. New chiral ionic liquids have been synthesised from the amino acid l-cysteine by straightforward routes. With these ligands, we have developed a chiral ionic system that includes chiral ionic liquids and their immobilisation in ionic solvents to provide a chiral supramolecular structure. These new catalytic systems were used in the enantioselective addition of alkylzinc to aldehydes and proved to be very efficient, capable of providing chiral secondary alcohols in excellent enantiomeric excesses and yields. This system also enabled the recycling of the ionic media and the ionic ligand, taking into account green chemistry considerations.
Enantioselective addition of diethylzinc to aldehydes catalyzed by o-xylylene-type chiral 1,4-amino alcohols with an aminal structure
Asami, Masatoshi,Hasome, Ayano,Yachi, Naoyuki,Hosoda, Naoya,Yamaguchi, Yoshitaka,Ito, Suguru
, p. 322 - 329 (2016/04/09)
A series of o-xylylene-type chiral 1,4-amino alcohols with an aminal structure was synthesized starting from (S)-2-(arylaminomethyl)pyrrolidine, o-bromobenzaldehyde, and a diaryl ketone. The enantioselective addition of diethylzinc to aldehydes was examined by using the 1,4-amino alcohols, and the corresponding chiral secondary alcohols were obtained with high enantioselectivities (up to 98% ee).
New atropisomeric amino alcohol ligands for enantioselective addition of diethylzinc to aldehydes
Faigl,Deák,Erdélyi,Holczbauer,Czugler,Nyerges,Mátrav?lgyi
, p. 216 - 222 (2015/03/18)
Efficient synthesis of several new atropisomeric amino alcohols having 1-phenyl-1H-pyrrole skeleton are reported. Steric arrangements of the products were confirmed by a single-crystal X-ray measurement. The consequences of the size of the N-substituents
Synthesis of quinazolinone-based aziridine diols as chiral ligands: Dual stereoselectivity in the asymmetric ethylation of aryl aldehydes Dedicated to Professor Dr. Metin Balci on the occasion of his retirement
Celik, Saffet,Cakici, Murat,Kilic, Hamdullah,Sahin, Ertan
, p. 152 - 157 (2015/02/19)
A new class of quinazoline-based enantiomerically pure aziridine diols 4a-d were prepared from the aziridination of mesityl oxide 3 with in situ generated 3-acetoxyaminoquinazolinone (S)-2b followed by NaBH4 reduction. Aziridine diols 4a-d were purified by means of column chromatography on silica gel and their stereochemistries were assigned by X-ray crystallography and NMR analysis. These aziridine diols 4 were evaluated as chiral ligands in the asymmetric addition of diethylzinc to aryl aldehydes, and ligand (S,R,R)-4a yielded (R)-1-phenylpropanol derivatives with up to 92% ee, while the diastereomer (S,S,R)-4c gave the opposite enantiomers (S)-1-phenylpropanol derivatives with up to 86% ee. The results demonstrate that switching the configuration of the aziridine alcohol moiety in ligand gives a remarkable reversal of enantioselectivity in the asymmetric addition of diethylzinc to aryl aldehydes.
Enantioselective addition of diethylzinc to aldehydes catalyzed by diastereomeric 1,4-amino alcohols with o-xylylene skeleton
Asami, Masatoshi,Nagai, Atsushi,Sasahara, Yukihiro,Ichikawa, Ken-Ichi,Ito, Suguru,Hosoda, Naoya
supporting information, p. 345 - 347 (2015/03/30)
Two diastereomeric 1,4-amino alcohols with o-xylylene structure (S,R)-2 and (S,S)-3, synthesized from chiral 1,4-diol (S,S)-1, were utilized as chiral ligands for the enantioselective addition of diethylzinc to aldehydes. The stereochemical outcome of the reactions was controlled solely by the absolute configuration of the benzylic carbon bearing amino group, and both enantiomers of 1-substituted propanol were obtained with up to 98% (S) and 96% (R) enantiomeric excesses.
Enantioselective addition of diethylzinc to aldehydes catalyzed by (R)-1-phenylethylamine-derived 1,4-amino alcohols
Asami, Masatoshi,Miyairi, Naomichi,Sasahara, Yukihiro,Ichikawa, Ken-Ichi,Hosoda, Naoya,Ito, Suguru
, p. 6796 - 6802 (2015/08/24)
A series of o-xylylene-type 1,4-amino alcohols, synthesized from (R)-1-phenylethylamine, were used as chiral ligands for the enantioselective addition of diethylzinc to benzaldehyde. (S)-1-Phenyl-1-propanol was obtained with high enantioselectivity in all cases since the stereochemical outcome of the reaction was controlled by the chiral benzylic carbon bearing amino group. Highest catalytic activity was obtained by using (R)-1-{2-[1-(pyrrolidin-1-yl)ethyl]phenyl}cyclohexan-1-ol (1n) derived from (R)-1-(1-phenylethyl)pyrrolidine and cyclohexanone. Various chiral secondary alcohols were obtained by the reaction of diethylzinc and aldehydes in the presence of 1n within 2 h with good to high enantioselectivities.
A new pyrrolidine-derived atropisomeric amino alcohol as a highly efficient chiral ligand for the asymmetric addition of diethylzinc to aldehydes
Faigl, Ferenc,Erdélyi, Zsuzsa,Deák, Szilvia,Nyerges, Miklós,Mátrav?lgyi, Béla
supporting information, p. 6891 - 6894 (2015/02/02)
A highly efficient pyrrolidine-derived atropisomeric amino alcohol, (Sa)-1-[2-diphenylhydroxymethyl-6-(trifluoromethyl)phenyl]-2-(1-pyrrolido)methyl-1H-pyrrole, has been synthesized as a chiral ligand for the enantioselective addition of diethylzinc to some prochiral aldehydes to afford (S)-alcohols. The conversion rates were close to quantitative with good to excellent enantiomeric excesses (up to 95% ee).
Asymmetric preparation of new N, N -dialkyl-2-amino-1,1,2-triphenylethanol catalysts and a kinetic resolution in the addition of diethylzinc to flavene-3-carbaldehydes
Kang, Seockyong,Baek, Jinho,Ko, Yikyung,Im, Chan,Park, Yongsun
supporting information, p. 630 - 634 (2013/04/23)
Enantiopure N,N-dialkyl-(S)-2-amino-1,1,2-triphenylethanols were prepared using a new synthetic methodology and tested for their ability to catalyze the enantioselective addition of diethylzinc to aldehydes. The structural modification of N-substituents of the catalysts led us to identify N-methyl-N-(S)-1-phenyl-ethyl-substituted 4d as an effective catalyst for the addition. Also disclosed is a kinetic resolution of racemic flavene-3- carbaldehydes with the chiral catalyst.
