title: Synthesis of novel enantiomerically pure tetra-carbohydrazide cyclophane macrocycles.
abstract: A total of twelve novel enantiomerically pure tetra-carbohydrazide cyclophane macrocycles have been synthesised in quantitative yields by reacting chiral (4R,5R)- and (4S,5S)-1,3-dioxolane-4,5-dicarbohydrazides with aromatic bis-aldehydes in a [2 + 2]-cyclocondensation reaction. The compounds show a dynamic behaviour in solution, which has been rationalized in terms of an unprecedented conformational interconversion between two conformers one stabilised by intramolecular hydrogen bonding and π-π stacking interactions.
authors.affiliation: School of Engineering and Science, Organic and Analytical Chemistry Laboratory, Jacobs University Bremen, Campus ring 1, P. O. Box. 750 561, 28725 Bremen, Germany. h.nour@jacobs-university.de
authors.forename: Hany F
authors.initials: HF
authors.lastname: Nour
authors.forename: Nadim
authors.initials: N
authors.lastname: Hourani
authors.forename: Nikolai
authors.initials: N
authors.lastname: Kuhnert