Catalytic Enantioselective Synthesis of α-(Benzylamino)cyclobutanones
作者:Nicola Melis、Lorenza Ghisu、Régis Guillot、Pierluigi Caboni、Francesco Secci、David J. Aitken、Angelo Frongia
DOI:10.1002/ejoc.201500460
日期:2015.7
An organocatalytic enantioselectivesynthesis of α-(benzylamino)cyclobutanones has been achieved by employing a tandem condensation/intramolecular rearrangement/proton transfer reaction and starting from racemic α-hydroxycyclobutanone and a selection of benzylamines. This reaction sequence afforded the products in good to high yields with moderate to high enantioselectivities.
Synthesis and Complexation Studies between Trifluoromethylammonium Threads and Dibenzo[24]Crown-8
作者:Carsten Johnsen、Paul C. Stein、Kent A. Nielsen、Andrew D. Bond、Jan O. Jeppesen
DOI:10.1002/ejoc.201001277
日期:2011.2
single-site ammonium thread enhances the binding strength between the DB24C8 ring and the ammonium thread. Investigations carried out between the double-site ammonium thread and DB24C8 reveal that the relative amount between the [2]pseudorotaxane and the [3]pseudorotaxane can be controlled by changing the ratio between the double-site ammonium thread and DB24C8. Quantitative studies carried out by NMR