Acetic Acid → 1-(3-Chloro-4-nitrobenzyl)-4-methylpiperazine

N-methyl piperazine (2.50 mL, 22.5 mmol) was added dropwise to a solution of 3-chloro-4-nitrobenzaldehyde (2.09 g, 11.3 mmol) and acetic acid (0.29 mL, 5.14 mmol) in toluene (11.7 mL) at room temperature. The reaction mixture was stirred for 1.5 h at room temperature before the addition of further toluene (4.4 mL) and sodium triacetoxyborohydride (3.58 g, 16.9 mmol). The reaction mixture was stirred at room temperature overnight and then quenched by the addition of MeOH (3 mL) and saturated aqueous NaHCO3 (23 mL). The reaction mixture was stirred for 30 min. The phases were separated and the aqueous layer was extracted with toluene (2×30 mL). The combined organic extracts were concentrated under reduced pressure and purified by flash column chromatography (EtOAc:MeOH:NEt3 9:1:0.1) to give the title compound (2.17 g, 71%) as an orange oil.

1. customquenched by the addition of MeOH (3 mL) and saturated aqueous NaHCO3 (23 mL)
2. stirringThe reaction mixture was stirred for 30 min
3. customThe phases were separated
4. extractionthe aqueous layer was extracted with toluene (2×30 mL)
5. concentrationThe combined organic extracts were concentrated under reduced pressure
6. custompurified by flash column chromatography (EtOAc:MeOH:NEt3 9:1:0.1)

ORD record

ord-fa22004cb70549f4aaf780cadbcd0b24

Source dataset

uspto-grants-2012_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08236954B2