反应详情

To a reaction mixture of methyl but-3-enoate (1.0 g, 10 mmol) and zinc-copper couple (2.0 g, 15.5 mmol) in DME (5 mL) and ether (30 mL) was added trichloroacetyl chloride (2.98 mL, 26.7 mmol) under N2 at rt. The reaction mixture was stirred at rt for 2.5 days. The reaction mixture was filtrated through diatomaceous earth (Celite®) and washed with DCM. The filtrate was concentrated and purified by 80 g silica gel cartridge which was eluted with a 20 min gradient of 0-60% EtOAc in hexane to yield methyl 2-(2,2-dichloro-3-oxocyclobutyl)acetate (1.0 g). 1H NMR (400 MHz, CDCl3) ppm 3.66-3.70 (3H, m), 3.42-3.55 (1H, m), 3.23-3.39 (1H, m), 3.05 (1H, dd, J=17.82, 8.78 Hz), 2.90 (1H, dd, J=16.94, 6.65 Hz), 2.67 (1H, dd, J=16.94, 8.16 Hz).

1. filtrationThe reaction mixture was filtrated through diatomaceous earth (Celite®)
2. washwashed with DCM
3. concentrationThe filtrate was concentrated
4. custompurified by 80 g silica gel cartridge which
5. washwas eluted with a 20 min gradient of 0-60% EtOAc in hexane