Abstract Treatment of 2, 6-di-tert-butyl-4-ethynylphenol with 2 equivalents of nBuLi, followed by addition of diaryl ketones, afforded the corresponding p-quinopropadienes 2a− f upon appropriate dehydrative treatments. These compounds are fairly stable, orange to purple, crystalline substances, exhibiting intense absorptions at longer wavelengths. In particular, the bis (dimethylamino) derivative 2a absorbs across the whole of the visible spectrum ...
