Asymmetric Imine Hydroboration Catalyzed by Chiral Diazaphospholenes
作者:Matt R. Adams、Chieh-Hung Tien、Robert McDonald、Alexander W. H. Speed
DOI:10.1002/anie.201709926
日期:2017.12.22
first use of diazaphospholenes as chiral catalysts has been demonstrated with enantioselective iminehydroboration. A chiral diazaphospholene prepared in a simple three‐step synthesis from commercial materials has been shown to achieve the highest enantioselectivity for the hydroboration of alkyl imines with pinacolborane reported to date. Enantiomer ratios of up to 88:12 were obtained with low (2 mol %)
Chiral N-Heterocyclic Carbene Borane Complexes: Synthesis and Structural Analysis
作者:Dipshikha Banerjee、Céline Besnard、E. Peter Kündig
DOI:10.1021/om201087n
日期:2012.1.23
A new family of chiralN-heterocycliccarbene borane complexes was synthesized starting from their corresponding imidazoliumsalts. The complexes were fully characterized. X-ray crystal structures of the complexes were obtained.
Chiral NHC Ligands for Enantioselective Gold(I) Catalysis Under Aerobic Conditions: the Importance of Conformational Flexibility and Steric Hindrance of NHC Ligand on Reactivity
of chiral NHC−Au−Cl complexes, bearing sterically encumbered NHC ligands, has been accessed by merging anilines with commercially available chiral aminoalcohols and amines. Evaluation of the catalytic activity in enantioselective allenol cyclization has pointed out the importance of the steric hindrance and conformationalflexibility of the NHC core for reactivity. Ion metathesis between NHC−Au−Cl
Preparation of enantiomers of 1-(1-naphthyl)-2,2-dimethylpropylamine and their behaviour as chiral solvating agents: study of diastereochemic association by Job's plots and intermolecular NOE measurements
作者:A Port、A Virgili、A Alvarez-Larena、J.F Piniella
DOI:10.1016/s0957-4166(00)00334-7
日期:2000.9
Enantiomers of 1-(1-naphthyl)-2,2-dimethylpropylamine have been obtained and considered as chiral solvating agents against several compounds. The formed complexes have been studied with the aid of the nuclear Overhauser effect and its stoichiometry by the method of continuous variations. Two diastereoisomeric complexes present similar geometry of association by pi-pi -stacking of the aromatic rings and by hydrogen bonding of the functional groups. (C) 2000 Elsevier Science Ltd. All rights reserved.