1: 1-bromo-2-methyl-4-vinylbenzene With n-butyllithium in tetrahydrofuran; hexane; Petroleum ether T=-78°C; 0.666667 h; 2: With sulfur in tetrahydrofuran; hexane; Petroleum ether T=-78 - -65°C; 3: acetic anhydride in tetrahydrofuran; hexane; Petroleum ether T=-75°C; 0.05 h; Further stages.;

1: Methyltriphenylphosphonium bromide With n-butyllithium in tetrahydrofuran T=0°C; 1.5 h; 2: 4-bromo-3-methylbenzaldehyde in tetrahydrofuran T=0°C; 2 h; Further stages.;

potassium hydrogensulfate

1: aluminium isopropylate; isopropyl alcohol 2: KHSO4 View Scheme