反应详情

To a suspension of 2-carboxy-3-chloro-5-methylthiophene (1.2 g, 6.6 mmol) in methylene chloride (16 mL) at 0° C. were added oxalyl chloride (0.6 mL, 7.3 mmol) and a drop of DMF. The mixture was stirred at ambient temperature for 5 hours, then concentrated of all volatiles and dried in vacuo to afford 1.3 g (quantitative yield) of 2-chlorocarbonyl-3-chloro-5-methylthiophene as a pale yellow solid; NMR (DMSO-d6/TFA) 7.4 (s, 1), 2.5 (s, 3) ppm.

1. concentrationconcentrated of all volatiles
2. customdried in vacuo