1.
Org Biomol Chem
; 16(10): 1770-1778, 2018 03 07.
Article
in English
| MEDLINE
| ID: mdl-29464253
ABSTRACT
Planar chiral [2.2]paracyclophane-based phosphine-phenol catalysts, which have a benzene ring spacer inserted between the pseudo-ortho-substituted [2.2]paracyclophanol 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.