1: 3,5-dimethoxy-phenol With AlCl3, aluminium chloride in carbon disulfide T=20°C; Friedel-Crafts acylation; 2: butyryl chloride in carbon disulfide T=0°C; Friedel-Crafts acylation; 12 h; 3: With hydrogenchloride in water pH=1; Cooling with ice;

1: 3,5-dimethoxy-phenol With AlCl3, aluminium chloride in carbon disulfide T=20°C; Friedel-Crafts acylation; 2: butyryl chloride in carbon disulfide Friedel-Crafts acylation; 12 h; Reflux; 3: With hydrogenchloride in water pH=1; Cooling with ice;