Hydrochloric Acid → ethyl 8-chloro-4-hydroxy-2-oxo-2',3',5',6'-tetrahydro-4H-spiro[naphthalene-1,4'-pyran]-3-carboxylate

HRID 1868940Notes

Reaction equation

[Cl:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4](/[C:8](/[OH:15])=[CH:9]/[C:10]([O:12][CH2:13][CH3:14])=[O:11])[C:3]=1[C:16]1([C:22](OCC)=[O:23])[CH2:21][CH2:20][O:19][CH2:18][CH2:17]1.CC[O-].[Na+].Cl>CCO.CCOC(C)=O>[Cl:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]2[C:3]=1[C:16]1([CH2:17][CH2:18][O:19][CH2:20][CH2:21]1)[C:22](=[O:23])[CH:9]([C:10]([O:12][CH2:13][CH3:14])=[O:11])[CH:8]2[OH:15]

Participants

Conditions

Temperature: 60 °C

Procedure

A mixture of (Z)-ethyl 4-(2-chloro-6-(3-ethoxy-1-hydroxy-3-oxoprop-1-enyl)phenyl)-tetrahydro-2H-pyran-4-carboxylate (0.38 g, 0.99 mmol) in 5 mL EtOH was treated with NaOEt (freshly made from 0.1 g Na and 5 mL EtOH), and stirred at 60° C. for 2 hours. The mixture was cooled to room temperature and diluted with 100 mL EtOAc, neutralized with 5N HCl to pH 5, washed with water (20 mL), saturated NaCl (20 mL), dried over anhydrous sodium sulfate and concentrated. The concentrate was purified by column chromatography (10-40% EtOAc/hexane) to give 0.27 g yellow solid. MS m/e: (M+H)+ 337.

Workup

temperatureThe mixture was cooled to room temperature
washwashed with water (20 mL), saturated NaCl (20 mL)
dry with materialdried over anhydrous sodium sulfate
concentrationconcentrated
customThe concentrate was purified by column chromatography (10-40% EtOAc/hexane)

Sources & evidence

ORD record: ord-05d9249ad98a4b828a33d99ec5771dec
Source dataset: uspto-grants-2009_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07635715B2

Reaction notes

Loading…