Arsenic Acid → 8-Methylquinoline-7-carboxylic acid

HRID 1643396Notes

Reaction equation

CC1NC(C)=C([CH:7]([C:9]2[CH:10]=[CH:11][CH:12]=[C:13]3[C:18]=2[N:17]=[CH:16][CH:15]=[CH:14]3)C)N=1.[As](=O)(O)(O)[OH:21].OCC([CH2:29][OH:30])O>S(=O)(=O)(O)O.O>[CH3:7][C:9]1[C:10]([C:29]([OH:30])=[O:21])=[CH:11][CH:12]=[C:13]2[C:18]=1[N:17]=[CH:16][CH:15]=[CH:14]2

Participants

Conditions

Temperature: 160 °C

Procedure

A mixture of 3-amino-2-methylbenzoic acid (18) (6.1 g, 39.7 mmol), arsenic acid (7.4 g, 52.3 mmol), and glycerol (5.8 mL, 79.4 mmol) in sulfuric acid (9 mL) was heated at 160° C. for 5 hours. The reaction mixture was cooled to room temperature and diluted with water. The mixture was filtered through a bed of celite and the filtrate was adjusted with 2 M NaOH to pH˜6. The aqueous layer was extracted numerous times with chloroform/isopropanol. The pooled organic layers were removed under vacuum. The solid residue was triturated with chloroform. The mixture was to filtered, and the solid was washed with hexane and dried under high vacuum to give 8-methylquinoline-7-carboxylic acid (19) 3.86 g (20.6 mmol, 52% yield).

Workup

temperatureThe reaction mixture was cooled to room temperature
filtrationThe mixture was filtered through a bed of celite
extractionThe aqueous layer was extracted numerous times with chloroform/isopropanol
customThe pooled organic layers were removed under vacuum
customThe solid residue was triturated with chloroform
filtrationto filtered
washthe solid was washed with hexane
customdried under high vacuum

Sources & evidence

ORD record: ord-84db67b7bd454ed786d2134b0f2f7375
Source dataset: uspto-grants-2012_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08119807B2

Reaction notes

Loading…