4- Bromo-6-methyl-1,2-dimethoxy benzene

Ethanone, 1- [3-(l,l-dimethylethyl)-4-methoxy-5-nitrophenyl Benzaldehyde, 2 (l,l-dimethylethyl)-4-methoxy-5-nitro Benzene, 1,4-BIS- (1, l-dimethylethyl)-2 methoxy-5-nitro Benzene, 1-(1, l-dimethylethyl)-2, 5-dimethoxy-4-nitro Benzene, 1-(1, l-dimethylethyl)-2-methoxy-4 methyl-5-nitro Benzaldehyde, 5- (1, l-dimethylethyl)-2-methyl-3-nitro Benzaldehyde, 2- (1, l-dimethylethyl)-4,5,6-trimethyl-3-nitro Benzene, 5-(l, l-dimethylethyl)-2-methoxy-l, 3-dinitro Benzene, 1-(1, l-dimethylethyl)-4-methoxy-2-methyl 3-5-dinitro Benzene, 2-bromo-5- (1, l-dimethylethyl)-4-methoxy-l,... 

The crude tertiary alcohol (5 g) was dissolved in 50 mL benzene and added to 107 g 90% sulfuric acid. The reaction mixture was stirred for 1 h at 0-2°C and then poured onto ice. After processing and evaporatively distilling at 150-155°C (0.15 mmHg), 1 g 2,5-dimethoxy-8-bromo-4a-methyl-10a-carbethoxy-l,2,3,4,4a,9,10,10a-octahydrophenanthrene was obtained. 

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