Improved Preparation of 5,6-Dialkoxy-l,l-dimethylindenes, Precocene Analogues Lacking the Pyranyl Oxygen Atom [1]
نویسنده
چکیده
The use of methanesulfonic acid as solvent and catalyst in the cyclocondensation of 1,2-dialkoxybenzenes with 3-methylbut-2-enoyl chloride to afford indanones 3, thus allowing the prepara tion of indenes 4 with improved overall yields, is reported. Additionally, structure of dimeric compound 7 a, formed in high yield by thermal treatment of 4a has been determined by combination of spectroscopic means and selective deuterations.
منابع مشابه
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