Three series of target compounds, 1-(ω-haloalkyl) imidazoles 3a-3e, bis-imidazoles 5a-5b and tri-imidazoles 6a-6b have been synthesized by the selective quaterisation of 1H-imidazole-1-propanenitrile (1) with α, ω-dihalide, bis(bromomethyl) benzene or tri(bromomethyl) benzene to obtain imidazolium salts, following by Hoffmann-type elimination.

The　procedures　are　described　involving　a　selective　Hofmanntype　elimination　of　the　2cyanoethyl　groups　from　the　bisimidazolium　salts　3　obtained　by　the　reaction　of　α,ωdihalides　2　with　1Himidazole1propanenitrile　1.

Using the –~CHR-(CH_2)_3-NFCH_3 (R = H, CH_3, CH_2CF_3, CHO, COCH_3) as the computational model, the two possible intramolecular reactions, nucleophilic substitution on nitrogen and elimination reaction, are studied at the theoretical level of MP2(full)/6-31+G(d,p).

The results indicated that de-esterification at low temperature(5℃) gave lessβ-elimination reaction,with better specific viscosity retained.

The results indicated that higher concentration of ammonia (4N) at low temperature (5℃) gives lessβ-elimination reaction, with better specific viscosity retained and increases the conversion of methoxyl groups to acid amide groups.

The heating elimination reaction in organic synthesis;

The component analysis of the eluate of gel chromatography and the β-elimination reaction results show that the protein in the enzymatic hydrolysate of rice protein is sugar-protein complex(glycoprotein) linked by N-glycoside peptide bond.

On the basis of the analysis of the mechanism of β-elimination reaction of haloalkyl,the influence regularity of the dissolvent polority for the reaction is discussed.

The results showed that low temperature(4 ℃) not only could reduce the β-elimination reaction which will impact pectin quality but also keep the viscosity of the product at a h.