4-Hydroxybenzaldehyde → p-((Trimethylsilyl)oxy)benzaldehyde

Beteiligte Stoffe

Reaktionsschritte

Triethylamine (42 ml) is added dropwise to a stirred solution of 4-hydroxybenzaldehyde (33.5 g) and chlorotrimethylsilane (42 ml) in ether (300 ml). After 15 min, the mixture is filtered through diatomaceous earth and the filtrate is concentrated and distilled in vacuo, providing 4-(trimethylsiloxy)benzaldehyde as a colorless oil (43 g). This material is reacted with methoxymethyl triphenylphosphonium chloride and potassium tert-butoxide in THF, using the procedure described in Example 1 (A) above, to provide 1-(2-methoxyethenyl)-4-(trimethylsiloxy)benzene (35%) as a colorless oil after distillation in vacuo, as a mixture of (E) and (Z) isomers. This material (3.0 g) is dissolved in methanol (30 ml) containing methanesulfonic acid (0.4 ml), and the solution is refluxed for 3 hr. Sodium bicarbonate (8 ml of 1.0N solution) is added, and the mixture is concentrated in vacuo. The residue is taken up in ethyl acetate, dried, and concentrated to provide 4-[(2,2-dimethoxy)ethyl]phenol as a pale red oil (2.4 g).

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