Synthesis Cementitious Properties. Alkoxy Benzoyl Hydrazine Hydrazone

Low molecular weight organogelators (LMOGs) have been an active research field in materials science and supramolecular chemistry due to their potential applications, involving optoelectronic devices, sensors, gel propellant. nanomaterials and delivery or modification agents for drugs. Hydrogen bonding interaction is considered as the major driving force of gelation for amide compounds such as amino acids, peptides, ureas, carbamates, and thioureas. This kind of LMOGs are generally composed of alkyl chain and one amide group (CONH) or two, together with acid moiety, hydroxyl moiety or amino group to ensure the formation of multiple intermolecular hydrogen bonding between neighboring molecules. To the best of our knowledge, the compounds containing only one amide group reported as LMOGs are few. Herein, three series of new LMOGs with an amide group have been designed and synthesized, and the corresponding gelation properties have been evaluated. The gelators consist of three parts:a hydrazone group functioning as a core linker, an alkoxybenzoyl group, and a bicyclohexyl moiety or phenyl group or alkyl group.The research includes the following parts:1. Five novel alkoxybenzoylhydrazones of 4'-propyl-1,1'-bicyclohexyl-4-one (3HHB-n) were designed and prepared as novel LMOGs with HPLC purities higher than 99%.3HHB-n was synthesized through three-step reactions, namely Williamson etherification. hydrazinolysis followed by the nucleophilic addition-elimination reaction, with overall yields more than 35%. The structures were confirmed by 1H-NMR and FTIR measurements. Their gelation behaviors in 28 solvents were tested.3HHB-n could form stable gels in bulk organic solvents and self-assemble into fibrous microstructures in organogel phase, especially in ethanol, isopropanol and acetonitrile. The SEM images demonstrated the presence of a 3D networks composed of intertwined fibers from ethanol and dendritic network structure from iso-propanol, with the diameters in the range of 1-6μm and the length of about tens of micrometers. Furthermore, the concentration dependence of the thermal stability of the gel had been confirmed.2. Twelve novel alkoxybenzoylhydrazones of aromatic aldehyde (YPBn) were designed and synthesized as novel LMOGs with HPLC purities higher than 99%. YPBn was prepared through nucleophilic addition-elimination reaction between alkoxy benzoyl hydrazine and series of aromatic aldehyde with yields more than 70%. Their structures were confirmed by 1H-NMR and FTIR measurements. Their gelation behaviors in 16 solvents were tested. The results showed that aromatic aldehyde with electron donor group such as methoxyl or hydroxyl group could help to enhanceπ-πeffect between benzene rings. The SEM images demonstrated that these LMOGs tend to form the lamellar structures when carbon number (n) of alkoxyl group is 12. FTIR and'H-NMR spectroscopy studies revealed that hydrogen bonding between the gelator molecules was one of the main driving forces for the formation of the gels.3. Four novel alkoxybenzoylhydrazones of aliphatic aldehyde (m-Bn) were designed and synthesized as novel LMOGs with HPLC purities higher than 99%. m-Bn was prepared through nucleophilic addition-elimination reaction between alkoxy benzoyl hydrazine and series of aliphatic aldehyde with yields more than 70%. Their structures were confirmed by 1H-NMR and FTIR measurements. Their gelation behaviors in 16 solvents were tested. m-Bn showed gelation ability in kinds of solvents. For example,12-B7 could gelated aniline,iso-propanol and other 10 solvents, and its minimum gel concentration (MGC) in isopropanol was 1%(w/v).4. The results showed that LMOG composed of hydrazone core group were able to self-assemble into ordered aggregates in a number of organic liquids and finally gelatinize the liquids through hydrogen bonding,π-πstacking interaction and van der Waals forces. Moreover, m-Bn displayed better gelation ability than the other series.