| An organic molecular cage is a type of discrete covalent molecules with intrinsic cavity.Their size tunability and solubility endow their potential applications of molecular separation,gas storage,catalysis and proton conductivity,etc.The porosity of a cage molecule is composed of intrinsic cavity and extrinsic channels,the latter resulting from crystal packing.However,cage-like structure may collapse after conventional heat treatment of porous materials before application,causing the decrease of porosity and the possibility of conversion into non-porous material.By directing the packing arrangement into different polymorphs,extrinsic channels connected to the cage windows may be changed,which leads to the alternation of porosity.Additionally,organic cages constructed from dynamic covalent bond are sensitive to acid or base.In this dissertation,a rigid organic cage that can be post-modified was synthesized in order to address the problems regarding material rigidity and chemical stability.In addition,an interlocked cage skeleton with chirality was synthesized,and an attempt was made to investigate its effect on the packing pattern during crystallization.Firstly,a rigid cage-like molecule MC with modifiable functional groups was designed and prepared by Glaser-Eglinton coupling reaction.The precursor was a claw-type molecule with sp3 hybrid carbon atom at the center and three alkynyl groups at the terminals,and a methoxy group which can be converted into hydroxyl group or carbon-carbon double bond through post-functionalization is also connected to the focal carbon atom.Another claw-type molecule similar to the precursor of MC,but with propynyl terminals was prepared as well.Through reversible alkyne metathesis reaction,an attempt was made to efficiently synthesize a rigid and modifiable cage molecule AM-MC.Secondly,a[4+6]interlocked cage was synthesized by the self-template effect of 1,3,5-triformylbenzene with a chiral diamine linker,and the exterior panels were selectively reduced by Na BH（OAc）3 to yield the interlocked cage CDC-R.The chiral center of the diamine linker was introduced by the reaction with a chiral dithiol.Six chiral centers of CDC-R were able to facilitate the cage to self-assemble in a more regular manner.The self-assembly of CDC-R was compared with that of its nonchiral homologue,and the correlation between the crystal structures and their chiral moieties was elaborated. |
