Water → Diphenylmethyl 7-t-Butoxycarbonyl-3-(Z)-1-propenyl-3-cephem-4-carboxylate

Beteiligte Stoffe

Reaktionsschritte

A mixture of diphenylmethyl 7-t-butoxycarbonyl-3-[(1-methyl-1,2,3,4-tetrazol-5-yl)thio]-3-cephem-4-carboxylate (IId, 0.125 g, 0.000215 mole), bis(dibenzylideneacetone)palladium (0.0062 g, 0.00001075 mole), triphenyl phosphine (0.0084 g, 0.000032 mole), zinc chloride (0.0586 g, 0.00043 mole) and Z-1-propenyltributyl stannane (0.071 g, 0.000215 mole) in dry tetrahydrofuran (2 mL) was refluxed under argon atmosphere for 20 h. After no further conversion of starting compound IId took place, water and ethyl acetate were added. The organic phase was separated, dried and concentrated. The crude product dissolved in acetonitrile and the acetonitrile solution was washed three times with equal volumes of pentane. Flash chromatography with 20% ethyl acetate in hexane gave the title product (0.022 g, 20%) as a foam. Also recovered was 0.0435g (34.8%) of starting compound IId.

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