Pyridine → 2,4-Dinitrobenzenesulfonamide

A solution of Part A compound (1.01 g, 2.37 mmol) and TFA (8 mL) in CH2Cl2 (30 mL) was stirred at RT for 4.5 h. The solution was concentrated in vacuo, and the residue was dissolved in CH2Cl2 and filtered through a pad of solid K2CO3. The filtrate was concentrated in vacuo to give the corresponding crude amine. To a solution of the crude amine in THF (11.9 mL) were added pyridine (0.383 mL, 4.74 mmol) and 2,4-dinitrobenzenesulfonyl chloride (0.85 g, 3.19 mmol) and the solution was stirred at RT for 15 h. Since some starting material still remained at this point, more sulfonyl chloride (0.32 g, 1.2 mmol) was then added. After a further 4 h, HPLC analysis indicated that all starting material had been consumed. The reaction mixture was diluted with Et2O, washed with 1N aq HCl, saturated aq NaHCO3 and brine, dried (MgSO4), filtered and concentrated in vacuo to provide the crude 2,4-dinitrobenzenesulfonamide

1. concentrationThe solution was concentrated in vacuo
2. dissolutionthe residue was dissolved in CH2Cl2
3. filtrationfiltered through a pad of solid K2CO3
4. concentrationThe filtrate was concentrated in vacuo
5. customto give the corresponding crude amine
6. additionwas then added
7. waitAfter a further 4 h
8. customhad been consumed
9. additionThe reaction mixture was diluted with Et2O
10. washwashed with 1N aq HCl, saturated aq NaHCO3 and brine
11. dry with materialdried (MgSO4)
12. filtrationfiltered
13. concentrationconcentrated in vacuo

ORD record

ord-12b792bebaa34945a1370bdf9a4c01e7

Source dataset

uspto-grants-2004_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06727271B2