Dichloromethane → HCID 10613124, compound

Participants

Reaction Conditions

Reaction Steps

The compound obtained in Preparation 33 (5 mmol; 1.65 g) is dissolved in 10 cm3 of acetic anhydride and the reaction medium is maintained at the reflux temperature of the solvent for 40 min. The excess anhydride is evaporated to dryness with a trolley pump in order to isolate the 2-methyl-4-[(2,7-dimethoxynaphth-1-yl)methyl]oxazolin-5-one, which is used without further purification. 30 cm3 of anhydrous CH2Cl2 and aluminum chloride (18 mmol; 2.37 g) are introduced into a three-necked flask placed under an inert atmosphere, followed by dropwise addition of 2-methyl-4-[(2,7-dimethoxynaphth-1-yl)methyl]oxazolin-5-one (6 mmol; 1.78 g) dissolved in 40 cm3 of the same solvent. The reaction medium is maintained at 60° C. for 2 h and, after cooling, is then poured onto an ice/concentrated HCl mixture and stirred for 1 h. The organic phase is recovered and the aqueous phase is extracted several times with CH2Cl2. The combined organic phases are dried over MgSO4 and then evaporated. The residue is purified by chromatography on a column of silica gel (particle size 60-200 μm); eluent: CH2Cl2 then CH2Cl2 :MeOH 99:1 v/v. N-(1-oxo-4,9-dimethoxy-2,3-dihydro-1H-phenalen-2-yl)acetamide (α) and N-(1-oxo-9-hydroxy-4-methoxy-2,3-dihydro-1H-phenalen-2-yl)acetamide (β) are obtained.

Provenance & Evidence