%0 Journal Article %A Martín, Angeles %A Pérez-Martín, Inés %A Quintanal, Luis M. %A Suárez, Ernesto %D 2007 %T Intramolecular 1,8- versus 1,6-Hydrogen Atom Transfer between Pyranose Units in a (1→4)-Disaccharide Model Promoted by Alkoxyl Radicals. Conformational and Stereochemical Requirements %U https://acs.figshare.com/articles/journal_contribution/Intramolecular_1_8_versus_1_6_Hydrogen_Atom_Transfer_between_Pyranose_Units_in_a_1_4_Disaccharide_Model_Promoted_by_Alkoxyl_Radicals_Conformational_and_Stereochemical_Requirements/3011185 %R 10.1021/ol070496q.s002 %2 https://acs.figshare.com/ndownloader/files/4712497 %K skeleton %K Transfer %K interglycosidic spiro ortho ester %K abstraction %K factor %K intramolecular hydrogen atom transfer %K derivative %K Conformational %K Pyranose Units %K Disaccharide %K Alkoxyl Radicals %K formation %K conformation %K disaccharide %K Stereochemical RequirementsThe stereochemical %K Promoted %K Model %K pyranose units %K transition %K Intramolecular %K trioxocane %X The stereochemical and conformational factors controlling the intramolecular hydrogen atom transfer (HAT) reaction between the two pyranose units in a (1→4)-disaccharide when promoted by a primary 6-O-yl radical are studied. Models with α-d-Glcp-(1→4)-β-d-Glcp or α-l-Rhamp-(1→4)-α-d-Galp skeletons lead exclusively to the abstraction of H−C-5‘ and the formation, through a nine-membered transition state, of a 1,3,5-trioxocane ring system in a stable boat-chair conformation. Notwithstanding, derivatives of α-l-Rhamp-(1→4)-α-d-Glcp abstract exclusively H−C-1‘ through a seven-membered transition state and therefore lead to an interglycosidic spiro ortho ester. %I ACS Publications