反应详情

11.4 g (0.3 mol) of sodium borohydride was added in one portion to a stirred solution of 111.5 g (0.5 mol) of diethyl 2,6-pyridinedicarboxylate in 1 litre of ethanol and stirred for 6 hours when a further 2.85 g (0.075 mol) of sodium borohydride were added and the mixture stirred overnight before being evaporated. The residue was dissolved in 800 ml dichloromethane and washed with water. The aqueous was extracted with 4×50 ml of dichloromethane. The combined organics were dried, evaporated and combined with the product from reaction 1 (13.1 g). The combined material was washed through a pad of silica on a large sinter with ethyl acetate (2 litres) which was evaporated and triturated with ether and filtered off to give 72.6 g of a white solid. The MLS (mother liquors) were evaporated and biotaged (chromatographed) [ethyl acetate/hexane (3:1)] to give a further 2.9 g of product.

1. additionwere added
2. custombefore being evaporated
3. dissolutionThe residue was dissolved in 800 ml dichloromethane
4. washwashed with water
5. extractionThe aqueous was extracted with 4×50 ml of dichloromethane
6. customThe combined organics were dried
7. customevaporated
8. customcombined with the product from reaction 1 (13.1 g)
9. washThe combined material was washed through a pad of silica on a large sinter with ethyl acetate (2 litres) which
10. customwas evaporated
11. customtriturated with ether
12. filtrationfiltered off