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Starting from pyridine-2,6-dicarboxylic acid (DPA), a series of novel pyridine-2,6-dicarboxylic acid derivatives were synthesized. In these compounds, 4-(hydroxymethyl)pyridine-2,6-dicarboxylate (4-HMDPA) and 4-[(bis-carboxymethyl-amino)-methyl]-pyridine-2,6-dicarboxylic acid (4-BMDPA) were used as multifunctional ligands to coordinate with Tb(III) and Eu(III) and the complexes were prepared. The fluorescence properties of the solid complexes and their solutions were investigated in detail. The results indicated that the weak election-withdrawing group 4-hydroxymethyl in 4-position of pyridine in 4-HMDPA could weaken the fluorescence intensity of the lanthanide complexes. The contradistinctive experimental results showed that the fluorescence intensities of these complexes are related to pH values of the aqueous solutions and the dipole moments of solvent molecules: in the neutral aqueous solutions, the fluorescence intensities of these complexes were strongest, while the dipole moments were lower when the fluorescence intensities were stronger. 4-BMDPA is the better sensitizer and may be used as time-resolved fluoroimmunoassay.

An important organic intermediate 4-hydroxymethylbenzophenone was synthesized by halogenation and hydrolyzation with phase transfer catalytic method using 4-methylbenzophenone as raw material and the technological conditions of reactions were investigated as well. Experimental results show that N-bromosuccinimide (NBS) is a good reagent to give 4-bromomethylbenzophenone undergoing a radical reaction with 4-methylbenzophenone with the yield of about 70.7%; 4-bromomethylbenzophenone can be hydrolyzed under basic conditions in the presence of phase transfer catalyst triethylbenzylammonium chloride for 5 h to give 4-hydroxymethylbenzophenone with yield of 84.4%. After the crude product is recrystallized from tetrahydrofuran (THF), the final product is obtained with purity above 99%. The structure of the titled compound is determined by infrared spectrum(IR), proton nuclear magnetic resonance (HNMR), and mass spectrum (MS) and elemental analysis (EA).

Nine 5-(β-substituted stylryl) salicyladehyde derivatives were prepared by PTC Witting reactions in the paper. The stereochemistry of the Witting reactions and the substituted effect on the UV spectra of salicyladehyde derivaties have been reported. It was observed that the spectra undergo a red shift as the conjugative effect of substituted becomes stronger. A good linear relationship between the shift of UV of p-substituted compounds and conjugation effect was obtained. It showed that the Hammett equation may be applied to the UV frequencies of the title compounds.