Inverse electron demand Diels-Alder carbohydrates

Boger, D L, Robarge, K D, A divergent de novo synthesis of carbohydrates based on an accelerated inverse electron demand Diels-Alder reaction of 1-oxa-1,3-butadienes, J. Org. Chem., 53, 5793-5796, 1988. 

Although inverse-electron demand Diels-Alder reactions are uncommon in the carbohydrate literature, a recent example reported by Chapleur and Euvard illustrates that this type of reactivity is accessible to certain carbohydrate derivatives (47). The addition of a vinyl ether to 65 gave a 78% yield of cycloadduct 66. 

The inverse electron demand hetero Diels-Alder reaction of 1-oxa-l,3-butadienes and electron-rich dienophiles is an extremely versatile tool in natural product synthesis. This cycloaddition represents the key step of numerous approaches not only to carbohydrates, but also to terpenes, alkaloids, polyethers, steroid derivatives and various biologically active metabolites. 

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