Synthesis
                    General procedure for the synthesis of 2-iodo-4-nitrobenzoic acid from the compound (CAS:112391-34-1): solid potassium iodide (55 g, 0.33 mol) was added in one go to a suspension of 2-iodo-4-nitrobenzoic acid I-1a (54.9 g, 0.18 mol) in water (250 mL) and glacial acetic acid (50 mL). Over the next 5-10 min, the solid gradually dissolved and the color of the solution changed from off-white to red. After stirring at 23 °C for 1 h, gaseous sulfur dioxide was passed into the reaction mixture until the red color disappeared and a light green suspension was formed. The solid product was collected by filtration and subsequently co-evaporated with toluene (3 x 250 mL) and finally dried under vacuum to give 2-iodo-4-nitrobenzoic acid I-1b (33 g, 64% yield).
                 
                
                    References
                    [1] Collection of Czechoslovak Chemical Communications,  1989,  vol. 54,  # 4,  p. 1012 - 1018
[2] Patent: US2004/122038,  2004,  A1. Location in patent: Page 14