Abstract
The halogenated benzenes, 1,2,4,5-tetrabromobenzene
6, hexabromobenzene
9, p-dichlorotetrabromobenzene
11, and 1,2-dibromo-4,5-dichlorobenzene
12, were investigated as 1,3-bis-, 1,4-bis-, and 1,3,5-tris-aryne precursors by using alkyllithiums and alkali metal amides as the metalating reagents. The arynes were trapped in Diels-Alder reactions with furan as the diene. The title compounds
3a/b are now readily available in two steps in 7% overall yield from 1,2,4,5-tetrabromobenzene
6.
The halogenated benzenes, 1,2,4,5-tetrabromobenzene
6, hexabromobenzene
9,
p-dichlorotetrabromobenzene
11, and 1,2-dibromo-4,5- dichlorobenzene
12, were investigated as 1,3-bis-, 1,4-bis, and 1,3,5-tris-aryne precursors by using alkyllithiums and alkali metal amides as metalating reagents. The arynes were trapped in Diels-Alder reactions with furan as the diene. The title compounds
3a/b are now readily available in two steps in 7% overall yield from 1,2,4,5-tetrabromobenzene
6.
