反应详情

To a solution of methyl trans-4-acetylamino-2,2-diethoxy-3,6-dimethyl-3,4-dihydro-2H-pyran-5-carboxylate (12.2 g) (Example 6) in 200 ml tetrahydrofuran was added 3.0 ml water and 1.0 ml 1N HCl. The mixture was stirred at 20°-25° C. for 16 hours, then neutralised by adding 1.0 g anhydrous potassium carbonate. The mixture was filtered and the filtrate evaporated at reduced pressure to give 11.4 g of crude product which was crystallised from toluene/hexane (50:50) giving ethyl 2-methyl-3-acetylamino-4-methoxycarbonyl-5-oxohexanoate (6.8 g), m.p. 93°-6° C.

1. filtrationThe mixture was filtered
2. customthe filtrate evaporated at reduced pressure
3. customto give 11.4 g of crude product which
4. customwas crystallised from toluene/hexane (50:50)