氟烷磺酰氟/双氧水/碱/丙酮体系与苄醇衍生物的氧化反应

Oxidation of Fluoroalkanesulfonyl fluoride/hydrogen peroxide/base/acetone System with Benzyl Alcohol Derivatives

研究了氟烷磺酰氟/双氧水/氢氧化钠/丙酮体系与6个苄醇衍生物的氧化反应,其中氟烷磺酰氟包括HCF2CF2OCF2CF2SO2F,n-C4F9SO2F和n-C8F17SO2F.最优反应条件为n(苄醇衍生物)∶n(氟烷磺酰氟)∶n(双氧水)∶n(氢氧化钠)=1∶4∶8∶8,溶剂为丙酮,反应温度为20℃,反应时间为24 h.产物酮的收率为23%～92%.探讨了该氧化反应的机理,原位生成的氟烷基过氧磺酸中间体可将丙酮氧化为二甲基二氧杂环丙烷,进而将反应体系中共存的苄醇衍生物氧化成相应的产物酮.氟烷磺酰氟/双氧水/氢氧化钠/丙酮体系原位生成的二甲基二氧杂环丙烷氧化苄位羟基的能力和传统的Oxone/CH3COCH3体系相当.本研究提供了一种新颖的原位制备二甲基二氧杂环丙烷的方法.

Oxidation of fluoroalkanesulfonyl fuoride/hydrogen peroxide/base/acetone system with six benzyl alcohol derivative substrates was reported. Fluoroalkanesulfonyl fluorides（ RfSO2F） include 5-H-3-oxa-1,1,2, 2,4, 4, 5,5-octafuoropentanesulfonyl fluoride （ HCF2 CF20CF2 CF2 SO2 F ）, perfuorobutanesulfonyl fluoride （ n-CaF9SO2F） and perfluorooetanesulfonyl fluoride （ n-C8Fa7802F）. The optimized reaction condition was n （Substrate） ： n（ RfSO2F） ： n（ HzO2 ） ： n（NaOH） = 1 ： 4 ： 8 ： 8, solvent was acetone, reaction temperature was 20 ~C and reaction time was 24 h. Yield of product ketones was 23%--92%. A plausible mechanism was proposed. Experimental results showed that in-situ generated fluorinatedalkano persulfonic acid intermediate could efficiently oxidize acetone and resulted dimethyl dioxirane could oxidize benzyl alcohol derivatives yiel- ding corresponding ketones. The oxidizing ability of fluoroalkanesulfonyl fluoride/hydrogen peroxide/base/ace- tone system for the oxidation of benzyl alcohol derivatives is similar to that of the traditional Oxone/CH3COCH3 system. A novel method for the in-situ generation of dimethyl dioxirane was developed.