155433-35-5Relevant academic research and scientific papers
Synthesis and utilization of trifluoromethylated amino alcohol ligands for the enantioselective Reformatsky reaction and addition of diethylzinc to N-(diphenylphosphinoyl)imine
Xu, Xiu-Hua,Qiu, Xiao-Long,Qing, Feng-Ling
, p. 7353 - 7361 (2008/12/20)
A series of trifluoromethylated amino alcohol ligands, which had been designed and conveniently prepared, were successfully applied in the enantioselective Reformatsky reaction and addition of diethylzinc to N-(diphenylphosphinoyl)imine, respectively. The influence of the substituents on C-3 position and the amino moiety on the enantioselectivity has been carefully investigated. In the best cases, ligand 1b exhibited good selectivity for the enantioselective Reformatsky reaction in 86% ee and ligand 12d provided excellent enantioselectivity in the addition of diethylzinc to N-(diphenylphosphinoyl)imine with 95% ee.
Chiral ferrocenyl amino alcohols as catalysts for the enantioselective borane reduction of ketones
Brunin, Thierry,Cabou, Jerome,Bastin, Stephanie,Brocard, Jacques,Pelinski, Lydie
, p. 1241 - 1243 (2007/10/03)
The catalytic asymmetric borane reduction of prochiral ketones was examined in the presence of chiral oxazaborolidine catalysts prepared in situ from chiral ferrocenyl amino alcohols. The corresponding chiral secondary amino alcohols were obtained with modest to high enantiomeric excesses (up to 90%) using (1S,2S)-2-amino-1-ferrocenyl-3,3-dimethyl-1-butanol 5c.
Diastereoselection during 1,2-Addition of the Allylindium Reagent to α-Thia and α-Amino Aldehydes in Aqueous and Organic Solvents
Paquette, Leo A.,Mitzel, Thomas M.,Isaac, Methvin B.,Crasto, Curtis F.,Schomer, William W.
, p. 4293 - 4301 (2007/10/03)
The stereochemistry of the indium-promoted reaction of allyl bromide with α-thia (PhS and MeS), disubstituted α-amino (Bn2N, Me2N, isoindolyl), and protected α-amino aldehydes (Ac and Boc) in water has been evaluated. The reactions involving the sulfur derivatives are minimally diastereoselective, indicating that the allylindium reagent is not thiophilic. Chelation is not observed and π-facial discrimination is achieved via Felkin - Ahn transition states under the steric control of the substituents. The Garner aldehyde is also anti-diastereoselective. Interestingly, N-acetylmannosamine is appreciably responsive to chelation control and is capable of generating 90% of the syn β-amino alcohol when reacted in a 0.5 M NH4Cl solution. While the α-dibenzylamino substituent is too bulky to enter into complexation, the α-dimethylamino group is not and can lead to high levels (99%) of syn diastereomer. The size of other neighboring substituents does have an impact on π-facial discrimination in these systems and can erode the stereoselectivity accordingly.
