1: Methyltriphenylphosphonium bromide With n-butyllithium in tetrahydrofuran T=-78°C; 0.25 h; 2: 2-isopropoxy-3-nitrobenzaldehyde in tetrahydrofuran T=-78 - 20°C; Wittig olefination;

1.1: K2CO3; Cs2CO3 / dimethylformamide / 0.17 h / 20 °C 1.2: dimethylformamide / 40 °C 2.1: n-BuLi / tetrahydrofuran / 0.25 h / -78 °C 2.2: tetrahydrofuran / -78 - 20 °C View Scheme