Assertion: polysaccharide's group | /r/HasProperty | useful
Facets:
value: at the secondary positions of monosaccharides
type: LOCATION
value: at the primary positions
type: LOCATION
Source sentences:
text: Leaving groups that are useful at the primary positions include bromide, iodide, less reactive sulfonates, or phosphonium leaving groups generated in situ (in Mitsunobu and related reactions).
text: Leaving groups that are useful at the secondary positions of monosaccharides are triflates and epoxides, but nucleophilic displacement at the secondary positions has hardly been exploited in the polysaccharide series, with only a rare example of a well-defined epoxide-opening reaction by an oxygen nucleophile (see below).