65481-84-7Relevant academic research and scientific papers
Racemization versus retention of chiral information during the formation of silicon and tin complexes with chiral Schiff base ligands
Warncke, Gisela,B?hme, Uwe,Günther, Betty,Kronstein, Martin
, p. 46 - 52 (2012)
Chiral Schiff base ligands with O,N,O′-coordination ability have been prepared with amino acid esters from the chiral pool. Unfortunately the chiral information is lost during the formation of complexes with these chiral ligands with silicon tetrachloride
Effect of substituents on enantioselectivity in chiral oxazaborolidine mediated asymmetric ketone reduction reaction
Balakrishnan,Ananthi,Velmathi
experimental part, p. 1157 - 1164 (2011/10/13)
Various new chiral ligands have been synthesized by the condensation of different esters of L-Valine with different substituted salicylaldehydes in order to find the most effective catalyst for the enantioselctive ketone reduction. Chiral amine synthesized from L-Valine methyl ester and 5-chloro salicylaldehyde is found to catalyse the enantioselective reduction of prochiral ketone with high yield (99%) and enantiomeric excess (91%) with 20 mol% of the catalyst using borane dimethylsulphide as a stoichiometric reducutant. Different subsituted prochiral ketones have also been reduced in high yield upto 90% and the corresponding secondary alcohols are formed with good enantiomeric excess upto 99%. The mechanism of this reduction can be very well explained by considering a plausible mechanism for the CBS catalyst.
Synthesis of novel chiral auxiliaries
Narasimhan,Swarnalakshmi,Balakumar,Velmathi
, p. 1666 - 1669 (2007/10/03)
A simple and easy route for the preparation of the higher homologue of oxazaborolidine namely dihydrooxazaborin has been reported. Also, the preparations of new bicyclic oxazaborolidines are reported.
Chemoselective reductive amination of aldehydes and ketones by dibutylchlorotin hydride-HMPA complex
Suwa, Toshihiro,Sugiyama, Erika,Shibata, Ikuya,Baba, Akio
, p. 789 - 800 (2007/10/03)
Reductive amination of various aldehydes and ketones has been performed effectively by pentacoordinate chloro-substituted tin hydride complex, Bu2SnClH-HMPA. The tin reagent worked particularly well for the case using weakly basic aromatic amines as starting substrates. Stoichiometric amounts of a substrate and a reducing agent were adequate for the reaction. The Sn-Cl bond in the complex plays an important role for both steps of imine formation and subsequent reduction. Highly chemoselective reduction of carbonyls could be achieved regardless of other functionalities such as halogen, carbon- carbon double bond and hydroxyl groups in the starting carbonyls and amines.
X=Y-ZH Systems as Potential 1,3-Dipoles. Part 8. Pyrrolidines and Δ5-Pyrrolines (3,7-Diazabicyclooctenes) from the Reaction of Imines of α-Amino Acids and their Esters with Cyclic Dipolarophiles. Mechanism of Racemisation of α-Amino Acid
Amornraksa, Kitti,Grigg, Ronald,Gunaratne, H. Q. Nimal,Kemp, James,Sridharan, Visuvanathar
, p. 2285 - 2296 (2007/10/02)
Imines of α-amino acid esters with aromatic, heterocyclic, and aliphatic aldehydes generate azomethine ylides stereospecifically by a prototropic shift on heating in toluene.The azomethine ylides undergo cycloaddition to N-phenylmaleimide, maleic anhydrid
