Sulfuryl chloride → HCID 20327955, compound

To a suspension of 4-nitroanthranilic acid methyl ester (16.5 g, 84 mmol) in glacial acetic acid (500 mL), a solution of sulfuryl chloride (13.6 g, 0.1 mol) in glacial acetic acid (20 mL) was added dropwise. The homogeneous mixture was stirred at room temperature for 18 h and the solvent was evaporated in vacuo. The residue was dissolved in CH2Cl2 (200 mL) and washed with saturated NaHCO3 (100 mL) and water (100 mL). The organic layer was dried over Na2SO4, filtered, and concentrated. The 1H NMR spectrum of the crude compound revealed the formation of a mixture of products, namely the desired 5-chloro regioisomer, and the byproducts 3-chloro regioisomer and the 3,5-dichlorinated compound. The crude mixture was purified by flash chromatography (silica gel, gradient 30-100% hexanes/CH2Cl2) to afford the desired 5-chloro-4-nitroanthranilic acid methyl ester (7.1 g, 36%) as a pale yellow solid.

1. customthe solvent was evaporated in vacuo
2. dissolutionThe residue was dissolved in CH2Cl2 (200 mL)
3. washwashed with saturated NaHCO3 (100 mL) and water (100 mL)
4. dry with materialThe organic layer was dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. additionthe formation of a mixture of products
8. customThe crude mixture was purified by flash chromatography (silica gel, gradient 30-100% hexanes/CH2Cl2)

ORD record

ord-e7d2036c59f94647adcc71c588b098b3

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08809326B2