Reaction #355755

Reaction equation

9-Ethylcarbazole-3-carbaldehyde

N-phenylhydrazine

→

9-Ethyl-3-carbazolecarboxaldehyde N-Phenylhydrazone

Solvents

methanol

methanol

Conditions

Workup

1. 1
   TemperatureThe reaction mixture was refluxed for 2 hours
2. 2
   OtherYellowish crystals were separated by filtration
3. 3
   Washwashed with a large amount of methanol
4. 4
   Otherdried
5. 5
   OtherThe infrared absorption spectrum of the product
6. 6
   Otherthe following absorption frequencies (KBr windows, in cm−1)

Procedure

9-Ethylcarbazole-3-carbaldehyde (10 g, 0.045 mol, from Aldrich, Milwaukee, Wis.) was dissolved in 300 ml of methanol under mild heating. Then, a solution of 7.25 g (0.067 mol) of N-phenylhydrazine (obtained from Aldrich) in methanol was added. The reaction mixture was refluxed for 2 hours. Yellowish crystals were separated by filtration, washed with a large amount of methanol and dried. The yield of the product, 9-ethyl-3-carbazolecarboxaldehyde N-phenylhydrazone, was 13.12 g (92%). The product had a melting point of 136-137° C. The 1H-NMR spectrum (100 MHz) of the product in CDCl3 was characterized by the following chemical shifts (δ, ppm): 1.34 (t, J=7.0 Hz, 3H, CH3); 4.23 (q, J=7.0 Hz, 2H, CH2); 6.90-7.64 (m, 8H, Ar); 7.60 (s, 1H, Ar); 7.81 (dd, 1H, Ar); 8.08 (d, 2H, Ar); and 8.15 (d, 1H, ═CH). The infrared absorption spectrum of the product was characterized by the following the following absorption frequencies (KBr windows, in cm−1): ν(N—H) 3306, ν(C—H) 2972, ν(arene C—H) 3051, ν(C═C, C—N in Ar) 1602; 1494; 1475; 1237, ν(C—N) 1256, γ(Ar) 815; 747; 731. The mass spectrum of the product was characterized by the following ions (in m/z): 314 (90%, M+1); 222 (100%, H5C2-C12H7N—CH═NH).

Source