861102-71-8Relevant academic research and scientific papers
Fragmentation of carbohydrate anomeric alkoxyl radicals: New synthesis of chiral 1-fluoro-1-halo-1-iodoalditols
Francisco, Cosme G.,Gonzalez, Concepcion C.,Kennedy, Alan R.,Paz, Nieves R.,Suarez, Ernesto
supporting information; experimental part, p. 6704 - 6712 (2009/07/01)
A new general methodology for the synthesis of 1,1,1-trihaloalditols by starting from l,5-anhydro-2-deoxyhex-1-enitol derivatives (glycals) is described. The halogens are introduced sequentially in each of the three different steps of the process. The fluorine is introduced in the first step by electrophilic fluorination of the starting glycal; next, hydroxyhalogenation of the resulting vinyl fluoride allows the addition of any halogen (F, Cl, Br or I) at will, and finally, an iodine atom is inserted through an alkoxyl radical fragmentation reaction. This methodology allows the preparation of diverse types of 1,1,1-trihalogenated compounds (R-CF2I, R-CFI2, R-CFClI and R-CFBrI) under mild conditions compati ble with sensitive substituents. In some cases, the diastereomeric mixtures generated from R-CFClI and R-CFBrI can be chromatographically separated, and their configuration determined by X-ray crystallographic analysis. The synthetic usefulness of these compounds has been preliminarily assessed by examining the reactivity of the fluorinated radical generated by rupture of the C-I bond.
