Carbon Dioxide → 6-Methoxy-2-Naphthoic Acid

HRID 1194503Notes

Reaction equation

Br[C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[CH:8]=[C:7]([O:12][CH3:13])[CH:6]=[CH:5]2.C([Li])(C)(C)C.[C:19](=[O:21])=[O:20]>C1COCC1>[CH3:13][O:12][C:7]1[CH:8]=[C:9]2[C:4](=[CH:5][CH:6]=1)[CH:3]=[C:2]([C:19]([OH:21])=[O:20])[CH:11]=[CH:10]2

Participants

Conditions

Temperature: -78 °C

Procedure

A solution of 8.00 g (33.8 mmol, Aldrich) of 6-bromo-2-methoxynaphthalene in 75 ml of dry THF was cooled to -78° C. and 36 ml (1.8M in pentane, 65 mmol, Aldrich) of t-butyllithium was added over 30 minutes. The reaction mixture was stirred for 30 minutes at -78° C. then warmed to -20° C. for 30 minutes. The mixture was recooled to -78° C. and b 8.00 g (180 mmol) of crushed dry ice was added to the slurry, and then this was allowed to warm to room temperature over 2 hours. The mixture was concentrated in vacuo, 100 ml of 1N HCl was added to the residue and this was extracted with 100 ml of hot EtOAc. The organic layer was washed with water, dried (MgSO4) and concentrated in vacuo to give a solid. Purification via recrystallization (EtOAc/petroleum ether) afforded 5.80 g (85%) of the title compound as small white needles: m.p. 198°-200° C.

Workup

temperaturethen warmed to -20° C. for 30 minutes
customwas recooled to -78° C.
temperatureto warm to room temperature over 2 hours
concentrationThe mixture was concentrated in vacuo, 100 ml of 1N HCl
additionwas added to the residue
extractionthis was extracted with 100 ml of hot EtOAc
washThe organic layer was washed with water
dry with materialdried (MgSO4)
concentrationconcentrated in vacuo
customto give a solid
customPurification
customvia recrystallization (EtOAc/petroleum ether)

Sources & evidence

ORD record: ord-3027e06d51af4308bec5cb4ab9b026d5
Source dataset: uspto-grants-1989_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04814454

Reaction notes

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