反应详情

A well-stirred solution of 28 (6.13 g, 30 mmol), mercaptoacetic acid (4.14 g, 3.13 ml, 45 mmol) and p-TsOH. H2O (60 mg, 0.31 mmol) in dry toluene was refluxed for 2 hours. Solvent was occasionally removed with a Dean-Stark trap, and fresh dry toluene was added. After cooling to room temperature, the reaction mixture was diluted with AcOEt (50 ml) and successively washed with: concentrated NaHCO3 (2×100 ml) and brine (2×100 ml), dried, filtered and evaporated to afford 25 (5.2 g, 25.5 mmol, 85%) as a yellow liquid that was used in the next step without any further purification.

1. customSolvent was occasionally removed with a Dean-Stark trap, and fresh dry toluene
2. additionwas added
3. additionthe reaction mixture was diluted with AcOEt (50 ml)
4. washsuccessively washed with: concentrated NaHCO3 (2×100 ml) and brine (2×100 ml)
5. customdried
6. filtrationfiltered
7. customevaporated