Planar chiral [2.2]paracyclophane-based phosphine–phenols: use in enantioselective [3 + 2] annulations of allenoates and <i>N</i>-tosylimines
作者:Shinji Kitagaki、Kento Nakamura、Chiharu Kawabata、Asuna Ishikawa、Naoko Takenaga、Keisuke Yoshida
DOI:10.1039/c8ob00248g
日期:——
skeleton and the diarylphosphino group, are highly suitable for enantioselective [3 + 2] annulations of allenoates and N-tosylimines. These catalysts can be tuned by changing the substituent on the benzene rings of the diarylphosphino group. The observed enantioselectivity of 92% is the highest reported to date for phosphine-catalyzed annulations of unsubstituted allenic esters and N-tosylaldimines.
The invention is to a compound exhibiting neurokinin inhibitory properties, a pharmaceutical composition comprising same and a method of treatment for neurokinin-mediated conditions.
The use of chiral, binaphthyl-based phosphepines as catalysts improves previous results for the enantioselective [3+2] cyclisation reactions between allenic esters and N-tosylimines, both in terms of conversion rate and enantioselectivity. Pyrrolines bearing 1-naphthyl, phenyl, o-tolyl and p-MeO-phenyl substituents on the stereogenic alpha-carbon have been obtained with enantiomeric excesses up to 64-80%. (c) 2007 Elsevier Ltd. All rights reserved.