220665-70-3Relevant academic research and scientific papers
Formation of quaternary chiral centers by N-Heterocyclic carbene-CuCatalyzed asymmetric conjugate addition reactions with grignard reagents on trisubstituted cyclic enones
Kehrli, Stefan,Martin, David,Rix, Diane,Mauduit, Marc,Alexakis, Alexandre
supporting information; experimental part, p. 9890 - 9904 (2010/11/04)
The copper-catalyzed conjugate addition of Grignard reagents to 3-substituted cyclic enones allows the formation of all-carbon chiral quaternary centers. We demonstrate in this article that N-heterocyclic carbenes act as efficient chiral ligands for this transformation. High enantioselectivities (up to 96% ee) could be obtained for a variety of substrates.
Synthesis of phosphoramides for the lewis base-catalyzed allylation and aldol addition reactions
Denmark, Scott E.,Su, Xiping,Nishigaichi, Yutaka,Coe, Diane M.,Wong, Ken-Tsung,Winter, Stephen B. D.,Choi, Jun Young
, p. 1958 - 1967 (2007/10/03)
Both chiral and achiral phosphoramides of diverse structure were prepared from diamines by the coupling to phosphorus(V) or phosphorus(III) reagents. Several enantiopure 1,2-diphenyl-1,2-ethanediamine analogues have been prepared by the reductive coupling of the corresponding N-silylimine with NbCl4(THF)2 and subsequent resolution by the formation of diastereomeric menthyl carbamates. (S,S)-N,N'-Di-(1-naphthyl)-1,2-diphenyl- 1,2-ethanediamine 15 was prepared by the arylation of (S,S)-1,2-diphenyl- 1,2-ethanediamine with naphthyl iodide.
