349451-17-8Relevant academic research and scientific papers
Development of Non-C2-symmetric ProPhenol Ligands. the Asymmetric Vinylation of N-Boc Imines
Trost, Barry M.,Hung, Chao-I,Koester, Dennis C.,Miller, Yan
supporting information, p. 3778 - 3781 (2015/08/18)
The development and application of a new generation of non-C2-symmetric ProPhenol ligands is reported herein. Rational design of the ProPhenol ligand paved the way to the first catalytic and asymmetric vinylation of N-Boc imines via hydrozirconation giving rise to valuable allylic amines in excellent yields and enantioselectivities. The utility of this method was demonstrated by developing the shortest reported asymmetric synthesis of the selective serotonine reuptake inhibitor (SSRI) (-)-dapoxetine.
Dimethylzinc-mediated additions of alkenylzirconocenes to aldimines. New methodologies for allylic amine and C-cyclopropylalkylamine syntheses
Wipf, Peter,Kendall, Christopher,Stephenson, Corey R. J.
, p. 761 - 768 (2007/10/03)
Hydrozirconation of alkynes with zirconocene hydrochloride followed by in situ transmetalation to dimethylzinc provides access to reactive alkenyl organometallic reagents from readily available precursors. Upon addition of imines, 1,2-attack leads to synthetically useful allylic amine building blocks. In the presence of CH2I2 or CH2Cl2, the N-metalated allylic amide intermediate is cyclopropanated and C-cyclopropylalkylamines are formed in high yield and excellent diastereoselectivities favoring the anti products. The use of enynes as starting materials for this domino reaction provides conjugated biscyclopropanes and thus allows the stereoselective formation of five new carbon-carbon bonds. A transition state that explains the need for both zirconocene complex and alkyl zinc in the cyclopropanation reaction is proposed.
