219703-65-8Relevant academic research and scientific papers
New chiral Schiff base as a tridentate ligand for catalytic enantioselective addition of diethylzinc to aldehydes
Tanaka, Takanori,Yasuda, Yorinobu,Hayashi, Masahiko
, p. 7091 - 7093 (2007/10/03)
We have developed new chiral Schiff base catalysts for the enantioselective addition of diethylzinc reagents to aldehydes. The reaction of benzaldehyde with diethylzinc in the presence of 1 mol % of the chiral Schiff base catalyst proceeded to afford 1-phenyl-1-propanol in 96% enantiomeric excess (ee).
Asymmetric Carbon-Carbon Bond Forming Reactions Catalyzed by Chiral Schiff Base-Titanium Alkoxide Complexes
Hayashi, Masahiko,Inoue, Tetsuya,Miyamoto, Yasunori,Oguni, Nobuki
, p. 4385 - 4398 (2007/10/02)
The enantioselective addition of trimethylsilyl cyanide to a variety of aldehydes proceeded by the aid of a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases and gave the corresponding cyanohydrins in high optical yield (up to 96percent e.e.).A remarkable rate enhancement was brought about by the addition of the Schiff base to the titanium alkoxide mediated silylcyanation of aldehydes.This catalyst system also promoted the highly enantioselective reaction of diketene with aldehydes, which led to the formation of optically active 5-hydroxy-3-oxoesters.
Enantioselective Trimethylsilylcyanation of Some Aldehydes Catalyzed by Chiral Schiff Base-Titanium Alkoxide Complexes
Hayashi, Masahiko,Miyamoto, Yasunori,Inoue, Tetsuya,Oguni, Nobuki
, p. 1515 - 1522 (2007/10/02)
A variety of aldehydes (aromatic, heteroaromatic, α,β-unsaturated, and nonconjugate aliphatic aldehydes) has been trimethylsilylcyanated in highly enantiomeric excess (ee) with a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases.A remarkable rate enhancement was brought about by the addition of the Schiff base into the titanium alkoxide mediated silylcyanation of aldehydes.The chemical structure of chiral Schiff base-titanium alkoxide complexes is discussed based on their 13C NMR spectra, field desorption (FD) mass spectra, and molecular weights.
