Water → Methyl 2-(3-benzyl-2-thienyl)-3-methoxypropenoate

Beteiligte Stoffe

Reaktionsschritte

Potassium tert-butoxide (844 mg) was added in one portion to a stirred suspension of (methoxymethyl)triphenylphosphonium chloride (2.86 g) in ether (30 ml). The reaction mixture became red. After 20 minutes, a solution of methyl 2-(3-phenoxymethyl-2-thienyl)-2-oxoacetate (770 mg) in THF (lOml) was added in one portion and the red colour was discharged. The resulting mixture was stirred at room temperature for 30 minutes then poured into water. The organic and aqueous layers were separated, and the latter was extracted with ether. The combined organic layers were washed with water, dried, concentrated and chromatographed using a 1:1 mixture of ether and petrol as eluent to give (i) the (Z)--isomer of the title compound (230 mg, 27%) as a pale yellow oil, lR (film) 1710, 1625 cm-1, 1H nmr : see Table VII; and (ii) the (E)-isom-er of the title compound (80 mg, 9% yleId), also a Pale yeIIow oil, IR (film) 1700, 1620 cm-1, 1H nmr : see Table VII.

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