STUDY ON THE CATALYTIC ACTIVITIES OF LANTHANOID(III) TRIFLATES IN THEGLYCOSYLATION OF 1-O-METHOXYACETYL SUGAR

The catalytic activities of a series of lanthanoid(III) triflates in t he glycosylation of thoxyacetyl-2,3,4,6-tetra-O-benzyl-D-glucopyranose with 1-octanol (Eq. 1) were investigated. As shown in Table 1, the tr iflates of some heavy lanthanide(III) salts such as Tb (OTf)3, Ho(OTf) 3, Tm(OTf)3, and Yb(OTf)3 were found to be highly effective. However, there seems to be no clear correlation between the catalytic activity and either the ionic radius or the oxophilicity of the lanthanoid meta l ion.