@article{oai:kutarr.kochi-tech.ac.jp:00000248,
 author = {Nishiwaki, Nagatoshi and Kobiro, Kazuya and Hirao, Shotaro and Sawayama, Jun and Saigo, Kazuhiko and Ise, Yumiko and Okajima, Yoshikazu and Ariga, Masahiro},
 issue = {19},
 journal = {Organic & Biomolecular Chemistry},
 month = {},
 note = {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 1,2,4-oxadiazoles, which are expected to serve as precursors for the preparation of a variety of functional materials by the chemical transformation of the carbamoyl group. While conventional preparative methods for 1,2,4-oxadiazoles involve the cycloaddition of an electron-rich nitrile oxide with an electron-deficient nitrile or a nitrile activated by a Lewis acid, our method employs the complementary combination of an electron-rich nitrile and an electron-deficient nitrile oxide- the inverse electron-demand 1,3-cycloaddition. The DFT calculations using B3LYP 6-31G* supported the abovementioned inverse reactivity, and also suggested the presence of an accelerating effect by the carbamoyl group as a result of hydrogen bond formation with a dipolarophilic nitrile.},
 pages = {6750--6754},
 title = {Inverse electron-demand 1,3-dipolar cycloaddition of nitrile oxide with common nitriles leading to 3-functionalized 1,2,4-oxadiazoles},
 volume = {9},
 year = {2011}
}