Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List 3-Bromo-4-methyl-5-nitropyridine

3-Bromo-4-methyl-5-nitropyridine synthesis

5synthesis methods
-

Yield:69872-15-7 70%

Reaction Conditions:

Stage #1:diethyl malonate with sodium hydride in N,N-dimethyl-formamide at 0; for 0.5 h;
Stage #2:3-bromo-4-chloro-5-nitropyridine in DMF (N,N-dimethyl-formamide) at 20; for 1 h;

Steps:

94 3-bromo-4-methyl-5-nitropyridine (94a)
3-bromo-4-methyl-5-nitropyridine (94a) Diethyl malonate (3.84 mL, 25.3 mmol) was slowly added to a suspension of sodium hydride (1.01 g of a 60% suspension in oil, 25.3 mmol) in DMF (15 mL) at 0° C. and stirred 30 min until gas evolution ceased. 3-bromo-4-chloro-5-nitropyridine (3.00 g, 12.6 mmol) was added slowly, and the dark reddish-brown solution was stirred at room temperature for 1 hour. The reaction was carefully quenched with water and acidified to pH 1 with 1N HCl. The aqueous mixture was extracted with EtOAc (2*150 mL). The combined organics were washed with water (100 mL) and brine, dried (Na2SO4), filtered, and concentrated in vacuo. The residue was diluted with 4N HCl (50 mL) and the solution refluxed 16 hours. The mixture was cooled in an ice bath and basified to pH 7 with 50% NaOH. The aqueous mixture was extracted with EtOAc (3*100 mL) and the combined organics were washed with brine, dried (MgSO4), filtered and concentrated in vacuo to afford 94a (1.90 g, 70%) as a yellow solid. 1H NMR (300 MHz, CDCl3) δ 8.94 (s,1H), 8.97 (s,1H), 2.65 (s, 3H).

References:

PFIZER INC US2005/90529, 2005, A1 Location in patent:Page/Page column 82

FullText

3-Bromo-4-methyl-5-nitropyridine Related Search: