CrO3/SiO2固载氧化剂对脱氢枞胺衍生物B环的氧化

以硅胶作载体,制备了负载型CrO3/SiO2固载氧化剂,研究了CrO3/SiO2氧化剂对N-苯甲酰基脱氢枞胺定向氧化制备N-苯甲酰基脱氢枞胺-7-酮的反应特征,考察了溶剂种类、溶剂量、反应温度、CrO3负载量及氧化剂用量对产率的影响。结果表明,采用负载量为2 mmol/g的CrO3/SiO2固载氧化剂,氧化剂与N-苯甲酰基脱氢枞胺物质量之比为2∶1,以50 mL环己烷为溶剂,回流温度(80.7℃)下搅拌反应8 h,可将1 g(2.57 mmol)N-苯甲酰基脱氢枞胺氧化成N-苯甲酰基脱氢枞胺-7-酮,产率为60%。该氧化剂具有制备简单,可应用于各种烯丙位氧化的特点,且氧化选择性和产物得率相对较高,反应操作简单,提纯方便。

Oxidation on ring B of dehydroabietylamine derivatives using CrO3/SiO2 solid-supported oxidizing reagent

A supported oxidant CrO3/SiO2 was prepared by absorbing the CrO3 on silicon gel,and its oxidation characteristics was investigated for the oxidation of N-benzoyl-dehydroabietylamine to N-benzoyl-dehydroabietylamine-7-one in this paper.Effects of solvent types and quantities,reaction temperature,loading amount and oxidant dosage on the yield were examined.The test result indicated that N-benzoyl-dehydroabietylamine-7-one can be obtained with yield of 60 % by oxidation of 1 g(2.57 mmol) N-benzoyl-dehydroabietylamine in the present of 2 equimolar amount of CrO3/SiO2(loading amount 2 mmol/g) in 50 mL cyclohexane under the reflux temperature for 8 h.This reagent is easily prepared,it can be used in the field of allylic oxidation in relatively high oxidation selectivity,yields with simple procedure and easy purifications.