were successfully differentiated during a subsequent Friedel–Crafts‐type cyclization. The (−)‐morphine double bond was introduced at a late stage in our first‐generationsynthesis, but was formed at an earlier stage in the second‐generationsynthesis, resulting in a more efficientroute to the end product.
Formal synthesis of (−)-morphine from d-glucal based on the cascade Claisen rearrangement
作者:Hiroki Tanimoto、Ryosuke Saito、Noritaka Chida
DOI:10.1016/j.tetlet.2007.11.037
日期:2008.1
The formalsynthesis of (−)-morphine is described. The C-ring in morphine was prepared in an optically pure form from d-glucal using Ferrier’s carbocyclization reaction, and the vicinal tertiary and quaternary stereocenters in the C-ring were stereoselectively generated in a one-step reactionbased on the cascade sequential Claisen rearrangement of an allylic vicinal diol derivative. After the one-step