65698-41-1Relevant academic research and scientific papers
Control of the ring selectivity in Diels-Alder reactions of naphthazarins mediated by sulfur functions
Carmen Carreno,Garcia Ruano, Jose L.,Urbano, Antonio
, p. 3789 - 3792 (1994)
Ring selectivity of Diels-Alder reactions of naphthazarin thioderivatives with cyclopentadiene is controlled by choosing the adequate sulfur substituent: p-tolylsulfonyl and p-tolylsulfinyl (under BF3·OEt2 catalysis) derivatives give cycloaddition only on the C-6 substituted tautomer. The opposite ring selectivity (exclusive reaction on the C-2 substituted tautomer) is achieved in the reaction of the p-tolylsulfonyl derivative at -78°C.
