Reactions at Oxygen Atoms
2.1
163
⊡ Scheme 78
Acylation reactions of fully protected pyranoses
by anchimeric assistance from acyl groups at C-2. Accordingly, 2,3,4,6-tetra-O-acetyl-D-mannose furnishes a mixture of 1-O-benzoates in which the β-anomer predominates, a result that
is especially significant in view of the difficulties generally encountered in obtaining β-glycosides of D-mannose.
2.1
163
⊡ Scheme 78
Acylation reactions of fully protected pyranoses
by anchimeric assistance from acyl groups at C-2. Accordingly, 2,3,4,6-tetra-O-acetyl-D-mannose furnishes a mixture of 1-O-benzoates in which the β-anomer predominates, a result that
is especially significant in view of the difficulties generally encountered in obtaining β-glycosides of D-mannose.