Synthesis, Separation And Derivatization Of Semi-methyl Citrullus Ring

Some macrocyclic moleculars such as crown ethers,cyclodextrins,and calixarenes undergo rapid development and gradually slow down,while cucurbit[n]urils（commonly abbreviated as Q[n]or CB[n]）with their highly symmetric rigid structures and selective recognition have a tendency to come from behind.So far,members of cucurbit[n]urils family have cucurbit[5]uril（Q[5]）,cucurbit[6]uril（Q[6]）,cucurbit[7]uril（Q[7]）,cucurbit[8]uril（Q[8]）,cucurbit[10]uril（Q[10]）,twisted cucurbit[13]uril（tQ[13]）,twisted cucurbit[14]uril（tQ[14]）,twisted cucurbit[15]uril（tQ[15]）and a series of cucurbit[n]uril derivatives with novel structures and properties,such as the inverted cucurbit-[n]urils（i Q[n]s）,the chiral nor-seco-cucurbituril（ns-Q[n]s）,andthealkyl-substitutedQ[n]s,the hydroxyl-substituted Q[n]s.The cucurbit[n]uril with hydrophobic cavity,a high density of negative electron ports,and a positively charged outer wall,have a good prospect in host-guest chemistry as a host molecule,such as the application of cell imaging,the response of the host-guest chemistry,drug release and the surface modification of the cucurbit[n]urils host-guest chemistry.Thesynthesisofmethyl-substitutedcucurbiturilsderivedfrom3α-methyl-glycoluril is relatively simple,but the separation process of methyl-substituted cucurbiturils derived from 3α-methyl-glycoluril is more complicated due to the similar solubility of similar structures and homologs.Based on the former works,the following aspects were mainly explored in this paper:1)Synthesis,separation and structural characterization of methyl-substituted cucurbiturils derived from 3α-methyl-glycoluril;2)Derivation of methyl-substituted cucurbit[6]urils derived from 3α-methyl-glycoluril;3)Study on the interaction of methyl-substituted cucurbit[7]urils derived from 3α-methyl-glycoluril with phenanthroline hydrochloride.4)The rate of action and mode of action of methyl-substituted cucurbit[6]urils derived from 3α-methyl-glycoluril with alkyl diamine hydrochloride in different solvents.Study on the combined rate and combined mode of action of methyl-substituted cucurbit[6]urils derived from3α-methyl-glycoluril with alkyl diamine hydrochloride in different solvents.In view of the good solubility of the methyl-substituted cucurbiturils derived from 3α-methyl-glycoluril in water or dimethyl sulphoxide（DMSO）,a derivatization experiment was conducted on methyl-substituted cucurbit[6]urils derived from3α-methyl-glycoluril（HMeQ[6]）.There are two sites that can be alkylated or hydroxylated on the"waist"of each glycoluril unit in unsubstituted cucurbiturils,while there is only one on the"waist"of each glycoluril unit in HMeQ[6].The good solubility of HMeQ[6]in DMSO provides a favorable condition for derivatization without the add of dissolving guest molecules.Through the experimental investigation of the oxidation and allylation of HMeQ[6],an effective approach was found to functionalize the methyl-substituted cucurbiturils derived from3α-methyl-glycoluril without resorting to cosolvent molecules.In this thesis,the research was also carried out on the self-assembly system of the methyl-substituted cucurbit[7]urils derived from 3α-methyl-glycoluril（HMeQ[7]）with the phenanthroline molecules.The experimental results revealed that4,7-dimethyl-1,10-phenanthroline hydrochloride molecule is first incorporated into HMeQ[7]cavity in a"half-encapsulated"manner and more phenanthroline molecules are attached to HMeQ[7]port in an"external"manner.These behaviors are mainly due to the structure of 4,7-dimethyl-1,10 phenanthroline hydrochloride molecule and van der Waals forces and hydrogen bonds between HMeQ[7]and4,7-dimethyl-1,10-phenanthroline hydrochloride molecule.The 1,10-phenanthroline hydrochloride molecule is only incorporated into HMeQ[7]cavity in a"half-encapsulated"manner.The interaction of HMeQ[6]with the alkyl diamine hydrochloride revealed that the recating rate and mode of interaction of methyl-substituted cucurbit[6]urils derived from 3α-methyl-glycoluril with alkyl diamine hydrochloride in water are different from those in DMSO.In water,their combined rate is faster and interaction mode of action is relatively simple.However,there is a big difference in DMSO.Before heating,one part of butanediamine hydrochloride is incorporated into HMeQ[6]cavity in a"encapsulated"manner,another part of butanediamine hydrochloride NH₃⁺groups are located at the centers of the HMeQ[6]portals in"head-binding"manner.Except for butanediamine hydrochloride,the other alkyl diamine hydrochloride undergoes"encapsulated"manners.After heating at 80oC,butylenediamine hydrochloride and hexamethylene diamine hydrochloride undergoes"encapsulated"manners.Octanediamine hydrochloride performs two modes of action,"encapsulated"manner and"head-binding"manner respectively.The longer chain diamine hydrochloride forms a supramolecular polymer with 9 repeat units.