Carbene Reactivity of 4-Diazo-4<i>H</i>-imidazoles toward Nucleophiles and Aromatic Compounds Matthew R. Smith Alexander J. Blake Christopher J. Hayes Malcolm F. G. Stevens Christopher J. Moody 10.1021/jo902165w.s002 https://acs.figshare.com/articles/dataset/Carbene_Reactivity_of_4_Diazo_4_i_H_i_imidazoles_toward_Nucleophiles_and_Aromatic_Compounds/2805595 Carbenes derived from diazoimidazolecarboxylates <b>4</b> under thermal or photochemical conditions undergo O−H and N−H insertion reactions with alcohols and amines, respectively, in moderate yield, in competition with reduction in good H-donor solvents. Dichloromethane reacts to give the corresponding 4-chloroimidazole. Aromatic hydrocarbons are excellent traps for the imidazolylidene carbene and lead to a range of arylimidazole derivatives <b>7</b>. Reaction with pyridine leads to the first example of a pyridinium ylide <b>8</b> formed from an imidazolylidene carbene, whereas irradiation in hexafluorobenzene gives the imidazoazocine <b>11</b>, presumably by way of an initial norcaradiene intermediate. 2009-12-18 00:00:00 irradiation diazoimidazolecarboxylate Aromatic imidazoazocine Reactivity insertion hydrocarbon arylimidazole derivatives 7. Reaction pyridinium ylide 8 Carbene norcaradiene chloroimidazole Nucleophile solvent amines pyridine Diazo Dichloromethane CompoundsCarbene hexafluorobenzene imidazolylidene carbene trap