9-乙基四氢咔唑的合成工艺研究（文章加急）

Synthesis of 9-Ethyl Tetrahydro-Carbazole

摘要:

9-乙基四氢咔唑作为一种重要的精细化工合成中间体而得到广泛应用。本文以苯肼、环己酮为起始原料，经醋酸环化合成四氢咔唑（收率70.5%），再与溴乙烷经烷基化反应制得9-乙基四氢咔唑。获得了合成9-乙基四氢咔唑的最佳优化条件：n (四氢咔唑)：n (溴乙烷)： n (氢氧化钠)=1：4：1.5， m (四氢咔唑) ： m (碘化钾) =1：0.01，c（四氢咔唑）=0.50 mol/L，c（十六烷基三甲基溴化铵）= 2.5 x 10-3 mol/L，乙腈为溶剂，回流反应9 h，收率为86.0%。该路线与传统工艺（环己酮先经氯化再与N-乙基苯胺缩合）相比，可避免氯化副产物生成，反应易控制，更适合工艺生产。

Abstract:

Tetrahydro-carbazole was synthesized by cyclization reaction of phenyl-hydrazine and cyclo-hexanone with the yield of 70.5%. And 9-ethyl tetrahydro-carbazole was synthesized by alkylation of tetrahydro-carbazole with ethyl bromide. The structures of product were characterized by 1HNMR和13CNMR. The optimum reaction conditions for synthesis of 9-ethyl tetrahydro- carbazole were as follows: n(tetrahydro-carbazole) : n(ethyl bromide) : n(sodium hydroxide)=1:4:1.5, m(tetra- hydro-carbazole) : m(potassium iodide)=1:0.01, c(hexadecyl trimethyl ammonium bromide)=2.5×10-3 mol/L, c(tetrahydro-carbazole) =0.50 mol/L. The yield of 9-ethyl tetrahydro-carbazole was 86.0% under the optimum conditions in the solvent of acetonitrile for 9 h. Compared with the traditional process (chlorination of cyclohexanone with chlorine, followed by condensation）, the synthesis could avoid the formation of chlorinated by-products and is easily to be commercialized.