钌金属配合物催化的丁香酚双键异构反应

Selective Double Bond Isomerization of Eugenol Catalyzed by Ruthenium Metal Complexes

以RuCl3·3H2O和三苯基膦制备钌金属配合物催化剂,研究钌金属配合物催化剂在不同溶剂中对丁香酚异构化反应的催化效果。研究结果表明,它在醇类等极性非质子溶剂中效果较好,其中以乙醇为溶剂时,转化率为98.3%,选择性为94.1%。在以乙醇为溶剂的条件下,考察了反应时间、催化剂用量、溶剂用量对丁香酚异构反应的影响,得出适宜的反应条件为:在乙醇回流温度下反应时间3 h,催化剂用量0.5%(按丁香酚质量比),溶剂用量300%(按丁香酚质量比)。在此条件下异丁香酚转化率为98.8%,其中反式异丁香酚选择性94.8%,得到的产品香气更为纯正。此外,还用红外、XRD和扫描电镜对RuCl2(PPh3)3催化剂进行了表征,研究了RuCl2(PPh3)3催化剂合成异丁香酚的反应机理。

The RuCl2（PPh3）3 complex catalyst was prepared from RuCl3 · 3H2O and triphenylphosphine,and its catalytical effects on double bond isomerization of eugenol in different solvents were studied.The polar protic solvents such as ethanol worked better where the conversion of the isoeugenol was 98.3％ with 94.1％ selectivity of the trans-isomer.Effects of different factors,including reaction time,catalyst dosage and moles of solvent were studied.The results showed that the highest yield of isoeugenol was achieved under conditions of reaction time 3 hours,mass ratios of catalyst and ethanol to eugenol were 0.5％ and 300％ respectively.Under the above conditions,the conversion of isoeugenol was 98.8％ with 94.8％ selectivity of trans-isomer,and its fragrance was improved greatly.Structure of RuCl2 （PPh3）3 was characterized by FI-IR,XRD and SEM.A possible mechanism for this reaction was also studied.