A tandem oxidation–intramolecular Diels–Alder reaction

Hsien-Jen Wu, Kai Pan
1987 Journal of the Chemical Society Chemical Communications  
Oxidation of the furan (4) with pyridinium chlorochromate gave the intramolecular Diels-Alder cycloadduct (6) as the major product, presumably via the intermediate (5). f The ratio was determined by n.m.r. spectroscopy and column chromatography separation of the crude oxidation products. The alkene protons of the cis-isomer (7) resonate at 6 6.24 (s, 2H) whereas those of the trans isomer (8) resonate is at 6 6.90 (s, 2H). § The ratio was determined by n.m.r. spectroscopy. The yield (80%) was
more » ... yield (80%) was the total yield of (9) and (10) from (7).
doi:10.1039/c39870000898 fatcat:t4yaaw4tine35drawrq5qs5rxq