Study On Synthesis And Application Of Chiral Compound With Oxazoline Groups

Due to stable structure, better coordination ability and simple preparation, chiral oxazoline can be applied in chiral recognition as molecular "trap"; moreover, it have a large steric hinerance which can induced chiral induction effect in the polymerization. Therefore, two classes of compounds containing chiral oxazoline functional groups were well designed and synthesized. This paper mainly studied application of the chiral compounds containing oxazoline groups in chiral recognition and asymmetric polymerization. 1) The chiral compound 3,4-dimethylthieno[2,3-b]thiophene carrying two chiral oxazoline groups((S)-DTTO) was synthesized, which as a chiral fluorescent probe used in chiral and ion recognition. In the studied of chiral recognition,(S)-DTTO was discovered to exhibit enantioselective to mandelic acid. The enantioselective appear gradual upon addition of(R)- and(S)- mandelic acid in the range from 0 to 80 eq. The study found(S)-DTTO not noly exhibited high selectivity towards Cr3+ but also showed strong fluorescence quenching upon interaction with Cr2O72-. 2) Two novel optically active fluorene derivatives bearing chiral oxazole((S)-FIDH) were designed and synthesized. Treatment with butyllithium gave rise to chiral carbon anion initiators(Li-(S)-FIDH). We studied the influences of Li-(S)-FIDH on asymmetric homopolymerizations and copolymerization of N-substituted maleimide(RMI) by NMR, GPC, polarimeter, CD.a. In the research of homopolymerization, the influences of chiral initiator’ sturcture, monomer substituent size, chiral initiator composition ratio and solvent were studied. All obtained optically active polymers showed specific rotations. The research results indicated optical rotation of the obtained polymers were attributed to asymmetric induction of the chiral initiators. We also found the optically active of polymers was greatly influenced by the structure of chiral initiator, the molar ratios of(S)-FIDH and n-Bu Li and solvent.b. The effects of achiral ininitiator and chiral initiator(Li-(S)-1-FIDH) for copolymers were studied in the copolymerization of(R)-1-PEMI and RMI. The result showed that Li-(S)-1-FIDH plays the better asymmetric induction role on the copolymer when the monomer has special structures. It also suggested that the conformation of the obtained copolymers has stable helical structure in solution.In this paper, we successful synthesized two kinds of new compounds containing chiral oxazoline functional groups, and had a better results in chiral recognition and anionic polymerization. For the application of chiral oxazoline compounds opened a new road.