| Crown ether is an auto synthetic acceptor. New crown ether that can identify a metal ion and has better selectivity had designed to applicate to ions selectivity. Benzene ring in benzocrown ether has electron receptor effect can reduce complex ability to metal ions because of weakling the basicity of crown ether. Many sorts of Lariat ether with donor group were designed. Compared with matrix of crown ether, Lariat ether with donor group has better linkage and selectivity. There is a good path to design Lariat ether is donor group adhibited in benzene ring, which was valued by chemist.A series of benzocrown ether with substituting group were synthesized by pyrocatechol and phenol with glycol bis (p-toluene sulfonate). The substituent were adhibited in benzene ring, and, germinal substitutional pyrocatechol was synthesized by oxidation and reduction There are 8 germinal substitutional benzocrown ether which are 4,5-dimethylbenzo-12-Crown-4, 4,5-di-methoxylbenzo-12-Crown-4, 4,5-di ethoxylbenzo-12-Crown-4, 4,5-di-ethoxylbenzo-15-Crown-5, 4,4',5,5'-tetramethoxylbenzo-18-Crown-6, 4,4',5,5'-tetraethoxylbenzo-18-Crown -6,4,4',5,5'-tetramethoxylbenzo-24-Crown-8,4,4',5,5'-tetraethoxylbenzo -24-Crown-8 were synthesized by condensation reaction. Their structure were characterized by H1NMR, MS, IR and elemental analysis. The firstsix of compound product were not reported in literature.The selectivity to ions of 6 novel benzocrown ether was studied. The variation to absorption wavelength of novel benzocrown ether and their solution complexes were analysised, and their absorbance was compared. Their selectivity or identify to metal ions were evaluated qualitatively by researching their complex ability to metal ions by UV spectrum. The results indicate that the selectivity or identity to ions of substitutional benzocrown ether is not only related to the change in size of crown ether but also to position and size of substituent in benzene ring of benzocrown ether.
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