Formaldehyde → 1-(2-Hydroxyethyl)-4-methylpiperazine

A mixture of 1-(2-hydroxyethyl)piperazine (10.0 g, 76.8 mmol), 37% aqueous formaldehyde solution (11.5 ml, 154 mmol), 10% palladium carbon catalyst (1.0 g) and methanol (100 ml) was stirred for 13 hr at room temperature in a hydrogen atmosphere. The reaction mixture was filtrated and the filtrate was concentrated. To the obtained residue was added 2N hydrochloric acid, and the mixture was washed with diethyl ether (200 ml). Sodium hydroxide (16 g) was added to the aqueous layer to make the layer alkaline, and the mixture was extracted with chloroform (4×200 ml). The organic layer was dried over anhydrous sodium sulfate and concentrated to give the title compound (9.3 g, 84%) as a pale-yellow liquid.

1. filtrationThe reaction mixture was filtrated
2. concentrationthe filtrate was concentrated
3. additionTo the obtained residue was added 2N hydrochloric acid
4. washthe mixture was washed with diethyl ether (200 ml)
5. additionSodium hydroxide (16 g) was added to the aqueous layer
6. extractionthe mixture was extracted with chloroform (4×200 ml)
7. dry with materialThe organic layer was dried over anhydrous sodium sulfate
8. concentrationconcentrated

ORD record

ord-900d057defce4077830bd2ada7bbf803

Source dataset

uspto-grants-2003_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06610729B1