The cyclic ketone, 6,7-dimethoxy-2-tetralone, a versatile starting material
for many dopaminergic compounds, can be prepared practically, cost-effecti
vely and in good overall yield. The synthesis starts from readily available
3,4-dimethoxyphenylacetic acid. Ring iodination gave the 2-iodo-4,5-dimeth
oxy acid, which was converted to its methyl ester. Palladium (II)-catalyzed
Heck cross coupling afforded the expected unsaturated diester, which was t
hen catalytically hydrogenated. Dieckmann condensation, followed by careful
decarboxylation led to the desired 2-tetralone. Reagents used in subsequen
t reactions are inexpensive and readily available. This method appears prac
tical for large-scale synthesis of the target tetralone, compared with othe
r procedures reported in the literature.