反应详情

A solution of (E)-methyl 6-methyl-4-oxo-2-heptenoate (10 g) prepared as described in a) above and (para-toluenesulfonyl)methyl isocyanide (11.5 g) in a mixture of dry dimethyl sulfoxide (30 ml) and diethyl ether (30 ml) was added over one hour to sodium hydride (2.75 g of a 60% oil dispersion, 0.068 mol) stirred in dry diethyl ether (90 ml) under nitrogen. After a further hour saturated ammonium chloride solution was added and the mixture was extracted with ethyl acetate, which was washed well with water, dried, and evaporated to a gum. The gum was chromatographed with ethyl acetate-isohexane (2:3) to afford a solid (3.3 g) which was crystallised from ethyl acetate-cyclohexane to give the sub-title ester.

1. extractionthe mixture was extracted with ethyl acetate, which
2. washwas washed well with water
3. customdried
4. customevaporated to a gum
5. customThe gum was chromatographed with ethyl acetate-isohexane (2:3)