Enantioselective CuH-Catalyzed Anti-Markovnikov Hydroamination of 1,1-Disubstituted Alkenes
作者:Shaolin Zhu、Stephen L. Buchwald
DOI:10.1021/ja509786v
日期:2014.11.12
Enantioselective synthesis of β-chiral amines has been achieved viacopper-catalyzedhydroamination of 1,1-disubstituted alkenes with hydroxylamine esters in the presence of a hydrosilane. This mild process affords a range of structurally diverse β-chiral amines, including β-deuterated amines, in excellent yields with high enantioselectivities. Furthermore, catalyst loading as low as 0.4 mol% could
The silyl-cupration and stannyl-cupration of allenes
作者:Ian Fleming、Michael Rowley、Purificacíon Cuadrado、Ana M. González-Nogal、Francisco J. Pulido
DOI:10.1016/0040-4020(89)80069-9
日期:1989.1
The stoichiometric silyl-cupration of allene 7, followed directly by treating the intermediate cuprate with a proton, with a range of carbon electrophiles, and with chlorine gives the vinylsilanes 8–13. Alternatively, when iodine is the electrophile, the product is the vinyl iodide 16. This can then be metallated and treated with a proton or a range of
Diastereoselective synthesis of substituted prolines via 5-endo-trig cyclisations of aza-[2,3]-Wittig sigmatropic rearrangement products
作者:James C. Anderson、Elizabeth A. Davies
DOI:10.1016/j.tet.2010.04.095
日期:2010.8
3]-Wittig sigmatropic rearrangement products from α-aminoacidderivatives are susceptible to a rare nucleophilic 5-endo-trigcyclisations of an amine onto a non-conjugated vinylsilane in high yield and complete diastereocontrol. Five examples are presented, with cyclisation yields between 35 and 87%. A rationale for the stereoselectivity of the cyclisation is forwarded based upon the steric control factors
Highly Efficient and Enantioselective Cyclization of Aromatic Imines via Directed C−H Bond Activation
作者:Reema K. Thalji、Jonathan A. Ellman、Robert G. Bergman
DOI:10.1021/ja0394986
日期:2004.6.1
The first highly enantioselective catalytic reaction involving aromatic C-H bond activation is communicated. Enantioselective cyclization of aromatic ketimines containing alkenyl groups tethered at the meta position of an imine directing group has been achieved using 5 mol % [RhCl(coe)2]2 and 15 mol % of an (S)-binol-derived phosphoramidite ligand. Selectivities of up to 96% ee and up to quantitative
Developing new procedures for the synthesis of tetrahydropyrans in a very stereoselective manner is of great importance for the synthesis of THP-containing naturalproducts. Here, we report an interesting protocol for the synthesis of polysubstituted halogenated tetrahydropyrans by silyl-Prins cyclization of vinylsilyl alcohols, in which the nature of the Lewis acid determines the outcome of the process