Dimethyl Sulfoxide → methyl 4-[(2R)-2-formyl-3,4-dihydro-2H-chromen-6-yl]benzoate

To a solution of dimethyl sulfoxide (33 mg, 0.425 mmol) in methylene chloride (2 mL) at −78° C., was added 0.14 mL of 2 M oxalyl chloride (0.272 mmol). After the solution had stirred at this temperature for 10 minutes, a solution of methyl 4-[(2R)-2-(hydroxymethyl)-3,4-dihydro-2H-chromen-6-yl]benzoate (50 mg, 0.17 mmol) in methylene chloride (2 mL) was added dropwise and the resulting mixture was stirred at −78° C. for an additional 1.6 hours. At this time, triethylamine (0.14 mL, 1.02 mmol) was added to the mixture slowly, and then it was allowed to warm to room temperature over 15 minutes. The solution of desired product was used directly in following steps.

1. stirringthe resulting mixture was stirred at −78° C. for an additional 1.6 hours

ORD-Eintrag

ord-b5475f0ab04b44948ee6b195049fa0af

Quelldatensatz

uspto-grants-2004_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06699860B2