Gabapentin → Prop-2-enyl 2-[1-(aminomethyl)cyclohexyl]acetate;hydrochloride

HRID 2360194Notes

Reaction equation

[CH2:1]1[CH2:6][CH2:5][C:4]([CH2:11][NH2:12])([CH2:7][C:8]([OH:10])=[O:9])[CH2:3][CH2:2]1.[CH2:13](O)[CH:14]=[CH2:15].S(Cl)([Cl:19])=O>C(OCC)C>[ClH:19].[NH2:12][CH2:11][C:4]1([CH2:7][C:8]([O:10][CH2:15][CH:14]=[CH2:13])=[O:9])[CH2:3][CH2:2][CH2:1][CH2:6][CH2:5]1

Participants

Conditions

Temperature: 0 °C

Procedure

A dry 3 L, three-neck, round-bottomed flash fitted with a magnetic stirring bar and a 500 mL pressure-equalizing addition funnel is flushed with nitrogen gas. The flask is charged with gabapentin (171 g, 1.0 mol) and allyl alcohol (1 L, 852 g, 14.6 mol) and the entire mixture is cooled to 0° C. in an ice-water bath. Thionyl chloride (225 mL, 360 g, 3.0 mol) is added dropwise over a period of 1 h to the stirred solution. The reaction mixture is allowed to stir at room temperature for 16 h, then is diluted with ethyl ether (2 L) and cooled to 0° C. while stirring. After several minutes white crystals form, which are collected by filtration. The crude product is recrystallized from a 1/3 (v/v) mixture of ethanol and ethyl ether (2 L) to give the product as a white solid (220 g 88%). m.p.: 138-142° C.

Workup

customA dry 3 L, three-neck, round-bottomed flash fitted with a magnetic stirring bar and a 500 mL pressure-equalizing addition funnel
customis flushed with nitrogen gas
temperaturecooled to 0° C.
stirringwhile stirring
filtrationAfter several minutes white crystals form, which are collected by filtration
customThe crude product is recrystallized from a 1/3 (v/v) mixture of ethanol and ethyl ether (2 L)

Sources & evidence

ORD record: ord-8e199cac2cf54ae48f67a73d74aad7d8
Source dataset: uspto-grants-2014_04
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08686034B2

Reaction notes

Loading…