1,8-Hydrogen Atom Transfer Promoted by N-Radicals in (1→4)-O-Disaccharide Models

The nitrogen‐centered radical generated by reaction of an N‐sulfonamidate, attached to C‐6 of a hexopyranose in a disaccharide model, with (diacetoxyiodo)benzene (DIB) andiodine undergoes a novel regio‐ and stereoselective intramolecular 1,8‐hydrogen atom transfer (HAT) reaction to promote the functionalization of remote positions. The intramolecular 1,8‐hydrogen atom transfer (HAT) reaction between the two pyranose units in a (1→4)‐O‐disaccharide promoted by a primary 6‐N‐yl radical generated under oxidative conditions has beenstudied. This novel process occurs by a completely regio‐ and stereoselective route that allows the functionalization of remote positions without modifying the remainder of the disaccharide.