Diisopropylethylamine → 1-(3-methoxy-4-nitrophenyl)-N,N-dimethylpiperidin-4-amine

Temperature

70 °C

A 100 ml flask was charged with 4-fluoro-2-methoxy-1-nitrobenzene (5.13 g, 30 mmol), N,N-dimethylpiperidin-4-amine (4.23 g, 33.0 mmol) and N,N-dimethylformamide (60 ml). To the mixture was added N-ethyl-N-isopropylpropan-2-amine (10.45 ml, 60.0 mmol) and the mixture was heated at 70° C. overnight under nitrogen. The reaction mixture was concentrated under high vacuum and the residue was partitioned between brine (100 ml) and methylene chloride (100 ml) and the pH adjusted to ca. 12-14 with sodium hydroxide. The layers were separated and the aqueous layer was extracted with methylene chloride (3×100 ml). The combined organics were dried over sodium sulfate, filtered and adsorbed directly on to silica gel (ca. 25 g). This was split in two portions each of which was purified on a silica gel cartridge (150 g) eluted with a 2.5, 4.5, 6% 7N methanolic ammonia in methylene chloride step gradient. The combined product fractions were concentrated to provide the title compound. MS (DCI(+)) m/e 280.2 (M+H)+.

1. concentrationThe reaction mixture was concentrated under high vacuum
2. customthe residue was partitioned between brine (100 ml) and methylene chloride (100 ml)
3. customThe layers were separated
4. extractionthe aqueous layer was extracted with methylene chloride (3×100 ml)
5. dry with materialThe combined organics were dried over sodium sulfate
6. filtrationfiltered
7. customThis was split in two portions each of which
8. customwas purified on a silica gel cartridge (150 g)
9. washeluted with a 2.5, 4.5, 6% 7N methanolic ammonia in methylene chloride step gradient
10. concentrationThe combined product fractions were concentrated

ORD record

ord-0285048272194001b7543b4d087b5444

Source dataset

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08354422B2