The eight target compounds—3,4-diphenylfuroxan (1), 3,4-bis(pyridine-2 -yl)furoxan (2), 3,4-bis(pyridine-3 -yl)furoxan (3), 3,4-bis(pyridine-4 -yl)furoxan (4), 3,4-bis(pyrazine-2 -yl)furoxan (5), 3,4-bis(4 -methoxybenzene-1 -yl)furoxan (6), 3,4-bis(4 -chlorobenzene-1 -yl)furoxan (7), 3,4-bis(3 ,5 - dinitro-benzene-1 -yl)furoxan (8) were designed and synthesized by putting off hydrochloric, intramolecular dimeric cycliczation and nitration using chloride oxime-based compounds as primary substances. The structures of target compounds were characterized by IR, NMR, MS and elemental analysis. The effect of different substituents to dimeric cycliczation reaction was preliminarily investigated. It was found that the electron withdrawing ability of substituents was stronger, the structures of cyanide oxidation were more easily generated, and the yields of target products were higher. The effects of reaction temperature, deacidification agent, deacidification agent s concentration, reaction medium were studied using compound 5 as researchful object. The suitable reaction conditions were that reaction temperature was usually controlled at 2～10 ℃. Na₂CO₃ or KHCO₃ was usually chosen as deacidification agent, and controlling the concentration at 3%～5%. The reaction medium was chosen low-boiling-point agent. Under suitable conditions, the yields of target compounds were 64.7%, 71.3%, 70.0%, 71.1%, 75.6%, 58.1%, 59.4% and 42.7% respectively. The thermal performance of target compounds were studied using differential scanning calorimetry (DSC). Result show that the thermal stability of phenyl substituted derivatives were better than heterocyclic substituted derivatives.

Key words: 3,4-disubstituted furoxano derivatives, dimerization reaction, synthesis, effect, thermal performance