Inverse electron-demand 1,3-dipolar cycloaddition of nitrile oxide with common nitriles leading to 3-functionalized 1,2,4-oxadiazoles
作者:Nagatoshi Nishiwaki、Kazuya Kobiro、Shotaro Hirao、Jun Sawayama、Kazuhiko Saigo、Yumiko Ise、Yoshikazu Okajima、Masahiro Ariga
DOI:10.1039/c1ob05682d
日期:——
A carbamoyl-substituted nitrile oxide was generated upon treatment of easily available 2-methyl-4-nitro-3-isoxazolin-5(2H)-one with THF (not dried); the reaction proceeded efficiently even in the absence of any special reagents and reaction conditions. The nitrile oxide caused 1,3-dipolar cycloaddition with common aliphatic nitriles or electron-rich aromatic nitriles to afford 3-functionalized 1,2
处理易得的2-甲基-4-硝基-3-异恶唑啉-5(2 H)-四氢呋喃(未干燥); 即使没有任何特殊的试剂和反应条件,反应也能有效地进行。一氧化氮与常见的脂肪族腈或富电子芳族腈引起1,3-偶极环加成反应,生成3-官能化的1,2,4-恶二唑,它们有望用作制备各种功能性材料的前体,方法是氨基甲酰基的化学转化。传统的1,2,4-恶二唑制备方法包括将富电子腈与缺电子腈或被路易斯酸活化的腈环加成,而我们的方法采用了富电子腈与缺电子的一氧化氮-逆电子需求的1,3-环加成。