Iodonium ion generated in situ from N-iodosuccinimide and trifluoromethanesulphonic acid promotes direct linkage of ‘disarmed’ pent-4-enyl glycosides

Abstract
N-Iodosuccinimide and trifluoromethanesulphonic acid provide a powerful source of Iodonium ion which allows ‘disarmed’ pent-4-enyl glycosides that normally respond sluggishly to lodonium dicollidine perchlorate, to react rapidly and to exhibit stereodirection via neighbouring group participation of C-2 esters.