Study On The Synthesis And Property Of Some Aromatic Ring Amino-derivatives Of Dehydroabietic Acid

Dehydroabietic acid(DAA) is one of the isomerides in the renewable rosin. There are three chrial carbon atoms and steady stereoconformation in molecules of DAA. Like some natural drug, it has a diterpene structure with three ring's aromatic amine. For these reasons, DAA might be hopefully modified to some multifunctional derivatives which can be used as high added valuable products like novel fluorescence derivatization reagents and active but low toxic medicines through constructing deterocycle on the dehydroabietic acid's aromatic ring. It not only meet with the demand of green chemistry but also bring about favorable economical and social effects.(1) In this paper, four benzothiadiazoles were designed and synthesized from DAA.Their fluorenscence was measured with fluorescentλex/λem of 400, 407nm/491, 507nm for two 2,1,3-benzothiadiazoles and 293, 287nm/362, 372nm for two 1,2,3-benzothiadiazoles respectively. Compared with DAA's methyl ester, four benzothiadiazoles maximal excitation wavelengths and emission wavelengths are bathochromic shifted. Single crystal of 2,1,3-benzothiadiazole has been obrained and the crystal structure was analyed by X-ray. Besides, the influence of the donor group and the acceptor group on DAA's skeleton for the fluorescence was discussed.(2) Methyl 12-nitro-dehydroabietate and Methyl 13-nitro-deisopropyldehydroabietate were obtained respectively with nitric and sulphuric acids in different concentrations from methyl dehydroabietate. After catalytic hydrogenation, 12-aminodehydroabietate and 12-amino- deisopropyldehydroabietate were diazotized and were coupled, then eight novel azo compounds were obtained. In trichloromethane, their maximal UV-absorbing wavelengths were 420nm, 457nm, 454nm, 541nm, 493nm, 550nm, 549nm, 482nm respectively, Compared with DAA's methyl este with 220nm, the maximal UV-absorbing wavelengths of eight azo compounds are bathochromics shifted to 200nm, 237nm, 234nm, 221nm, 273nm, 330nm, 329nm, 262nm, respectively. These red or yelow bright-coloured products have good properties for exploiting novel pigment and dyes.In summary, 14 new compounds were synthesized and characterized by IR, NMR and MS in this paper. Our study shows that DAA's properties such as fluorescence, UV-absorbing were improved through constructing heterocycle and azo-group on DAA's aromatic ring. All that laid the groundwork for future exploitation of multifunctional reagents.