Regiospecific and Stereoselective Syntheses of (±) Morphine, Codeine, and Thebaine via a Highly Stereocontrolled Intramolecular 4 + 2 Cycloaddition Leading to a Phenanthrofuran System
posted on 2009-08-19, 00:00authored byGilbert Stork, Ayako Yamashita, Julian Adams, Gary R. Schulte, Richard Chesworth, Yoji Miyazaki, Jay J. Farmer
Total syntheses of the morphine alkaloids are described that use a direct stereoselective formation of the phenanthrofuran system via an intramolecular 4 + 2 cycloaddition of a diene tethered to the 4-position of a 7-methoxybenzofuran-3-carboxylic acid ester.