2-[3-Cyano-4,5,5-trimethylfuran-2(5H)-ylidene]malononitrile → HCID 72536678, compound

Participants

Reaction Steps

In a 100-mL round bottom flask with stirbar was added 4-(3-aza-tricyclo[3.2.1.02,4]oct-3-yl)-2,3,5,6-tetrafluoro-benzaldehyde (0.35 g, 1.23 mmol), 2-(3-cyano-4,5,5-trimethyl-5H-furan-2-ylidene)-malononitrile (0.39 g, 2 mmol), pyridine (5 mL) and acetic acid (several drops). The mixture was stirred under nitrogen at room temperature for 3 days. TLC showed that one red fluorescent product had formed as the main product. The reaction was stopped. The product mixture was poured into ice-water (500 mL) and vigorously stirred for 4 h. The crude products were extracted with CH2Cl2 (100 mL×5). The combined organic layer was dried over anhydrous MgSO4. After removing solvent, the crude organic product was adsorbed on silica gel, placed at the top of a silica column and eluted (hexane/EtOAc=2/1). Fraction containing only the first red fluorescent product were combined and concentrated to give a red solid, which was recrystallized from 1-propanol to give the final product as red needles. Mp 233° C. IR (neat): 2951, 2228, 1573, 1481, 1390, 1366, 1163, 1107, 983, 962 cm−1. 1H NMR (400 MHz, CDCl3): δ 7.64 (d, J=16.8 Hz, 1H), 7.23 (d, J=16.8 Hz, 1H), 2.70 (br s, 4H), 1.80 (s, 6H), 1.63-1.51 (m, 3H), 1.34-1.27 (m, 2H), 0.98-0.92 (m, 1H); 13C NMR (100 MHz, CDCl3): 176.4, 173.4, 148-139 (m), 132.5, 118.8 (t), 111.4, 110.6, 109.9, 97.6, 95.3 (m).

Provenance & Evidence