Asymmetric cyclopropanation of conjugated cyanosulfones using a novel cupreine organocatalyst: rapid access to delta(3)-amino acids

作者：Aitken Lewis S; Hammond Lisa E; Sundaram Rajkumar; Shankland Kenneth; Brown Geoffrey D; Cobb Alexander J A^*

来源：Chemical Communications, 2015, 51(70): 13558-13561.

DOI：10.1039/c5cc05158d

An organocatalytic asymmetric synthesis of a novel, highly functionalised cyclopropane system furnished with versatile substituents and containing a quaternary centre is described. The process utilises a new bifunctional catalyst based on the cinchona alkaloid framework and the products made using this catalyst were obtained as single diastereoisomers, with very high enantioselectivities (up to 96% ee). We have also demonstrated that these resulting cyclopropanes are very useful synthetic intermediates to interesting products, such as the difficult to access delta(3)-amino acids.

• 出版日期2015