3,4-二(3',5'-二硝基苯-1'-基)氧化呋咱的合成及热分解机理

摘要

3,4-Bis(3',5'-dinitrobenzene-1 '-yl) furoxan was synthesized via five-step reactions of oximation ,diazotization, denitrification,cyclization and nitration using benzonitrile as starting materials. The reaction conditions were optimized,and the cyclization could be performed at 2 ～ 10 ℃ within 3 h and Na2CO3 in excess of 20％ with a yield of about 64.7％. The product's structure was characterized by IR,NMR,MS and elemental analysis. In addition,the mechanism of the key reaction-cyclization was suggested. The vicarious nucleophilic substitution of hydrogen(VNS) reaction of the target compound was explored,and it could not go under the conditions applied by the authors. Furthermore,the thermal decomposition of this furoxan was studied with differential scanning calorimetry ( DSC), IR, and thermogravimetry/mass spectrum( TG/MS) ,and the related mechanism was proposed and analysed in detail. The initial step of decomposition is dissociation of N-O bond with coordination oxygen in furoxan ring.%以苯甲腈为原料,经肟化、重氮化、脱氮、环化及硝化五步反应合成了3,4-二(3',5'-二硝基苯-1'-基)氧化呋咱;利用红外光谱、核磁共振、质谱、元素分析等手段鉴定了化合物的结构;探索了此化合物的氢的亲核取代(VNS)反应;探讨了关键反应-氧化呋咱成环反应机理;优化了肟化、氧化呋咱成环及硝化的反应条件;利用差示扫描量热(DSC)等多种热分析手段研究了目标化合物的热分解机理.结果表明,氧化呋咱成环反应的最佳条件:Na2CO3为理论量的1.20倍,反应温度2～1 0℃,反应时间3 h,收率64.7%;目标化合物的热分解首先发生在氧化呋咱环含配位氧的N-O键.