N-Benzyl-l-prolinol: an efficient catalyst for the enantioselective addition of dialkylzinc reagents to N-(diphenylphosphinoyl)imines
作者:Raquel Almansa、David Guijarro、Miguel Yus
DOI:10.1016/j.tetasy.2007.03.026
日期:2007.4
Commercially available N-benzyl-l-prolinol has shown to be a very efficientcatalyst for the enantioselectiveaddition of dialkylzinc reagents to N-(diphenylphosphinoyl)imines. The use of 0.5 equiv of this β-aminoalcohol as a catalyst leads to the expected addition products in good yields and with ees up to 92% in a reaction time of only 4 h at room temperature. This ee is almost equal to the highest
Polymer-supported l-prolinol-based catalysts for the enantioselective addition of dialkylzinc reagents to N-(diphenylphosphinyl)imines
作者:Raquel Almansa、Juan F. Collados、David Guijarro、Miguel Yus
DOI:10.1016/j.tetasy.2012.12.007
日期:2013.2
Merrifield or Wang-type resins have been shown to form efficient catalysts for the enantioselective addition of dialkylzinc reagents to N-(diphenylphosphinyl)imines. The enantioselectivity achieved with the polymeric catalyst (ee up to 88%) is slightly lower than the one obtained with the homogeneous ligand N-benzyl-l-prolinol, but the polymer-supported ligand presents the advantage of its recyclability: it
General Method for the Expedient Synthesis of Salt-Free Diorganozinc Reagents Using Zinc Methoxide
作者:Alexandre Côté、André B. Charette
DOI:10.1021/ja710864p
日期:2008.3.1
Zn(OMe)2 with readily available Grignard reagents, it was possible to induce the complete precipitation of magnesium salts and then obtain salt-free diorganozinc reagents after centrifugation/filtration. This practical method to generate dialkylzincreagents as well as mixed diorganozinc reagents was successfully tested in various catalyticenantioselectivereactions, proving the purity of the product and
Asymmetric Synthesis of N-(Diphenylphosphinyl)amines Promoted by Chiral Carbosilane Dendritic Ligands in The Enantioselective Addition of Dialkylzinc Compounds to N-(Diphenylphosphinyl)imines
Asymmetric synthesis of N-diphenylphosphinoylamines by solvent-free enantioselective addition of dialkylzincs to N-diphenylphosphinoylimines
作者:Itaru Sato、Ryo Kodaka、Kenso Soai
DOI:10.1039/b106775n
日期:2001.11.15
Solvent-free enantioselective addition of dialkylzincs to N-diphenylphosphinoylimines in the presence of chiral 2-morpholino-1-phenylpropan-1-ol affords N-diphenylphosphinoylamines with up to 97% ee. The reaction in the solvent-free system is faster than in organic solvents.