δ-癸内酯的合成

Synthesis of δ-Decalactone from Dimethyl Adipate and 1-Bromopentane

采用廉价易得的己二酸二甲酯为原料 ,用金属钠在甲苯中进行Dieckmann酯缩合 ,加入DMF为溶剂在 80～ 85℃直接与溴代正戊烷反应生成 2 戊基 2 甲氧酰基环戊酮 (Ⅰ ) ,经过脱羧反应和Beayer-Villiger氧化反应得到δ 癸内酯 (Ⅲ ) ,产品纯度为w(δ 癸内酯 ) >98% (GC法 ) ,香气纯正。反应总产率达 48%。列出了各中间体的IR数据 ,最终产品由FT -IR、1

δ-Decalactone was prepared from cheap and easily obtainable raw material dimethyl adipate by Dieckmann ester condensation in the presence of metallic sodium suspended in toluene. After some azeotropic mixture was collected and most toluene distilled, DMF was added and 1-bromopentane was dropped at 80 - 85 °C. The reaction was carried out to give 2-amyl-2-methoxycarbonyl cyclopentanone. Then by decarboxylation and Beayer Villiger oxidation, δ-decalactone was gained. Purity of the product w(δ-decalactone) > 98% (by GC). The yield was over 48%. Structure of the product was confirmed by FT - IR, 1HNMR and EI - MS.