Chemical Properties
orange to yellow-brown powder
Uses
2-Amino-4-methyl-5-nitropyridine was used in the preparation of matrix mixture required to study new technical developments for the direct tissue analysis of peptides.
General Description
The crystal structure of 2-amino-4-methyl-5-nitropyridine was elucidated.
Synthesis
Example 9: Synthesis of 2-(1-aziridinyl)-4-carbamoyl-5-nitropyridine (Compound VI)
Reagents and conditions: (i) HNO3/H2SO4; (ii) NaNO2; (iii) POCl3; (iv) Na2Cr2O7; (v) SOCl2/DMF, followed by NH4OH treatment; (vi) aziridine.
Synthesis steps for compound 30:
1. cool concentrated sulfuric acid (240 mL) in an ice bath and slowly add raw compound 29 (2-amino-4-methylpyridine, 50 g, 0.462 mol), keeping the temperature at 0°C.
2. slowly add acid mixture prepared from concentrated sulfuric acid (98%, 55 mL) and concentrated nitric acid (72%, 55 mL) in a 1:1 volume ratio.
3. slowly heat to 50°C and react for 24 hours to ensure complete reaction.
4. Pour the reaction solution into 2 L of ice water, adjust the pH to 7 with a strong base, and filter to collect the precipitate.
5. Dry the filter cake to give 54 g of crude product.
6. The by-product 4-methyl-3-nitro-2-aminopyridine was removed by wet distillation and subsequently recrystallized in 95% ethanol to give 33 g of Compound 30 (2-amino-4-methyl-5-nitropyridine) with a melting point of 220-222 °C (Literature value: 220-222 °C).
Yield: 46.6%.
References
[1] Patent: EP2366691, 2011, A1. Location in patent: Page/Page column 12-13
[2] Patent: CN105906621, 2016, A. Location in patent: Paragraph 0044
[3] Patent: WO2005/97129, 2005, A2. Location in patent: Page/Page column 176
[4] Patent: WO2012/103806, 2012, A1. Location in patent: Page/Page column 43
