A 250 mL round-bottom flask fitted with a PTFE stopcock sidearm was charged with a suspension of salicylaldehyde (2.440 g, 20.0 mmol) and 4-aminopyridine (0.940 g, 10 mmol) in dry toluene (200 mL). A Soxhlet extractor equipped with a dry paper thimble charged with excess powdered CaH₂ and condenser was fitted. The condenser outlet was fitted with a T-joint allowing the reaction to be performed under an atmosphere of dry dinitrogen. The system was heated to reflux for 3 d. Toluene was removed to ca. 50 mL in vacuo under Schlenk conditions and the solution was left overnight. The resulting yellow precipitate was isolated by filtration (1.50 g, 75 %) and handled only under a dry atmosphere.

1H NMR (400MHz, CD3CN): ö12.70 (s, 1H, Ar-OH), 8.85 (s, 1H, CH=N), 8.65 (m, 2H, Py-CH), 7.60 (dd, ³J= 7.6 Hz, ⁴J = 1.6 Hz, 1H, ArH), 7.49 (m, 1H, ArH), 7.30 (m, 2H, Py-CH), 7.03 (m, 2H, ArH).

¹³C{¹H}NMR (100 MHz, CDCl3): δ 166.9 (CH=N), 160.8 (Ar-C_q), 155.0 (Py­C_q), 150.74 (Py-CH), 133.9 (Ar-CH), 133.1 (Ar-CH), 119.1 (Ar-C_q), 117.0 (Ar­C_q), 116.6 (Ar-CH), 115.9 (Py-CH).

MS(ESI) m/z 199.1 [M+H]⁺

Anal. Found (Calculated for C₁₂H₁₀N₂O): C 72.76 (72.71), H 5.23 (5.08), N 14.13 (14.13) %.