A convenient srn1 synthesis of aromatic nitriles from diazonium salts via diazosulfides

✍ Scribed by Giovanni Petrillo; Marino Novi; Giacomo Garbarino; Carlo Dell'erba

• Publisher: Elsevier Science
• Year: 1987
• Tongue: French
• Weight: 775 KB
• Volume: 43
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)86905-2

✦ Synopsis

Properly substituted diazosulfides XCsH,-N=N-SPh (Ll (either isolated or generated in situ from arenediazonium tetrafluoroborates and sodium benzenethiolate) react with tetrabutylamnonium cyanide, in MezSO under photon or electron stimulation, leading to nitriles XC,H,CN !zI. Sat isfactory yields ofi,comparable with those of the Sandmeyer reaction, are obtained when X = 3-or 4-CFs, 2-, 3-, or 4-CN, 4-F. 4-MeCO, 3&O, 4-NO,, 4-PhCO, and 4-PhSO,. For different reasons, the reaction practically fails as a useful nitrite synthesis when X = H, 4-MeO, 2-, or 3-NO,. The collec ted evidences agree well with the intervention of an S,,1 mechanism, to which diazosulfides I, given their easy reducibility followed by a prompt fragmentation of the C-N and N-S bonds, are convenient participating sub strates. An important consequence of the mechanism involved is the behal iour of bromo and chloro derivatives (J: X = Br, Cl' which lead, through the contemporaneous introduction of two cyano functionalities, to more than satisfactory yields of the corresponding dicyanobenzenes.