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IV. Unsaturated Carbohydrates That Undergo Radical Cyclization

  • Page ID
    24621
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    The unsaturated carbohydrates that undergo radical cyclization are an eclectic mixture of compounds in which the reactive multiple bond in each typically is electron-deficient. Reduced electron density in the multiple bond can be caused either by conjugation of this bond with a carbonyl group or by having an electronegative substituent attached to it. Ring forma­tion still can occur when a double or triple bond is not electron-deficient, but as described earlier in this Chapter (Section II), in such a situation cyclization is slower and less able to compete with other radical reactions.