Table 5.

Conversion of 4-(5-amino-4-cyano-1H-pyrazol-1-yl)-benzoic acid (1u) to 4-(4-cyano-1H-pyrazol-1-yl)-benzoic acid (2u) with various quantities of gallic and salicylic acid.

Catalyst Loading (mol%)	Conversion (%) Gallic Acid	Conversion (%) Salicylic Acid
0	0	0
1	0	0
5	33	1
10	26	26
10a	18	22
20	22	30
100	0	21

All experiments were: 4-(5-amino-4-cyano-1H-pyrazol-1-yl)-benzoic acid (1.0 mmol) and the stated quantity of gallic acid or salicylic acid in THF and iso-pentyl nitrite (1.2 mmol) in THF (50 mL), flow rate 1.0 mL min⁻¹, through a 10 mL coil reactor maintained at 70 °C, giving a residence time of 10 min. The conversions were calculated by integration of product ¹H-NMR peaks relative to a quantified internal standard of nitrobenzene. ^aReaction performed at 120 °C.