Acetyl chloride → 2-Acetyl-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid
Reaction equation
[OH-].[Na+].Cl.[CH2:4]1[C:13]2[C:8](=[CH:9][CH:10]=[CH:11][CH:12]=2)[CH2:7][CH:6]([C:14]([OH:16])=[O:15])[NH:5]1.[C:17](Cl)(=[O:19])[CH3:18]>CC(C)=O>[C:17]([N:5]1[CH:6]([C:14]([OH:16])=[O:15])[CH2:7][C:8]2[C:13](=[CH:12][CH:11]=[CH:10][CH:9]=2)[CH2:4]1)(=[O:19])[CH3:18]Participants
Procedure
To a mixture of acetone (75 mL) and 2N NaOH (100 mL) was added portionwise 1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid hydrochloride (10.00 g, 46.8 mmol). After stirring for 10 min, acetyl chloride (7.38 g, 94 mmol) in acetone (50 mL) was added slowly into the above solution, followed with 2N NaOH at room temperature. The reaction mixture was maintained at a pH>10 and stirred for 1 hour. The acetone was evaporated in vacuo and acidified the residue by adding 3N HCl. The separated solid was collected by filtration, washed several times with water, and dried to afford the known 2-acetyl-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid as an enantiomeric mixture, 7.90 g, (76.9%); mp 178-180° C. (170-171° C.):21 1H NMR (DMSO-d6) δ 2.15 (3H, s, Me), 3.02-3.24 (2H, m), 4.29-4.75 (2H, m), 4.98-5.17 (1H, m), 7.17-7.21 (4H, m, 4×ArH), 12.70 (1H, brs, exchangeable, OH); m/z219.0 (M+H)+.
Workup
- temperatureThe reaction mixture was maintained at a pH>10
- stirringstirred for 1 hour
- customThe acetone was evaporated in vacuo
- additionby adding 3N HCl
- filtrationThe separated solid was collected by filtration
- washwashed several times with water
- customdried
Sources & evidence
- ORD record
- ord-84f3ee01b8f9457d8b256a815eb6038d
- Source dataset
- uspto-grants-2013_04
- Patent number
- US08410130B2
Reaction notes
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