Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
Org Biomol Chem. 2011 Jul 21;9(14):5228-37. doi: 10.1039/c1ob05410d. Epub 2011 May 31.
1,3-Diphenylbenzo[e][1,2,4]triazin-7(1H)-one (6) reacts with tetracyanoethylene (TCNE) or tetracyanoethylene oxide (TCNEO) to give the deep green 2-[1,3-diphenylbenzo[e][1,2,4]triazin-7(1H)-ylidene]propanedinitrile (11) in 17 and 15% yields, respectively. Nucleophiles such as amines, alkoxides, thiols and Grignard reagents all reacted with the 1,3-diphenylbenzotriazinone 6 regioselectively at C-6, while halogenating agents reacted exclusively at C-8. Furthermore, 8-iodo-1,3-diphenylbenzo[e][1,2,4]triazin-7(1H)-one (32) undergoes palladium-catalysed Suzuki-Miyaura and Stille coupling reactions to give 8-aryl- or heteroaryl-substituted benzotriazinones. By combining both the C-6 and C-8 chemistries 1,3,6,8-tetraphenylbenzo[e][1,2,4]triazin-7(1H)-one (42) and 1,3-diphenyl-6,8-di(thien-2-yl)-benzo[e][1,2,4]triazin-7(1H)-one (43) can be prepared. All new compounds are fully characterized.
1,3-二苯基苯并[e][1,2,4]三嗪-7(1H)-酮（6）与四氰乙烯（TCNE）或四氰乙烯氧化物（TCNEO）反应，分别以 17%和 15%的产率得到深绿色的 2-[1,3-二苯基苯并[e][1,2,4]三嗪-7(1H)-亚基]丙二腈（11）。亲核试剂，如胺、烷氧基、硫醇和格氏试剂，都在 C-6 处对 1,3-二苯基苯并三嗪酮 6 进行了区域选择性反应，而卤化剂仅在 C-8 处反应。此外，8-碘-1,3-二苯基苯并[e][1,2,4]三嗪-7(1H)-酮（32）在钯催化的 Suzuki-Miyaura 和 Stille 偶联反应中经历，得到 8-芳基或杂芳基取代的苯并三嗪酮。通过结合 C-6 和 C-8 化学，可制备 1,3,6,8-四苯基苯并[e][1,2,4]三嗪-7(1H)-酮（42）和 1,3-二苯基-6,8-二（噻吩-2-基）-苯并[e][1,2,4]三嗪-7(1H)-酮（43）。所有新化合物均经过充分表征。
