1: 3-(methoxymethoxy)-2-(trimethylsilyl)fluorobenzene With n-butyllithium; potassium tert-butylate in tetrahydrofuran; hexane T=-75°C; 2 h; 2: carbon dioxide in tetrahydrofuran; hexane 3: With hydrogenchloride in water T=25°C; 6 h;

1.1: BuLi; KOtBu / tetrahydrofuran; hexane / 2 h / -75 °C 1.2: tetrahydrofuran; hexane 2.1: 3.24 g / HCl / H2O / 6 h / 25 °C View Scheme