Lanthanum trifluoromethanesulfonate

Other RE(OTf)3 were also examined as catalysts in the reaction of 1 with acetic anhydride (Table 2). Catalytic amounts of all the RE(OTf)3 listed effectively mediated the acylation of 1. Among these, scandium trifluoromethanesulfonate (scandium triflate, Sc(OTf)3)[6] or Yb(OTf)3 was superior to other RE(OTf)3 and afforded the acylation product 2 quantitatively. When, on the other hand, lanthanum trifluoromethanesulfonate (lanthanum triflate, La(OTf)3) was used, the yield of 2 was relatively low. The yields shown in Table 2 may reflect the catalytic activity of respective RE(OTf)3. 

Lanthanum trifluoromethanesulfonate was shown to promote an indium-mediated vinylogous Reformatsky coupling in water (Diana et al., 1996) ... 

Diana, S.-C.H. Sim, K.-Y. Loh, T.-P. (1996) Lanthanum trifluoromethanesulfonate [La(OTf)3] promoted indium-mediated coupling of ethyl 4-bromocrotonate with carbonyl compounds in water, Synlett, 263-4. 

Lanthanum(III) trifluoromethanesulfonate is obtained by reaction of La2(CO,), with triflic acid in water followed by dehydration. 

In another attempt the surface of SBA-15 was modified with a tether molecule containing a sulfhydryl group and the resulting thiol moiety that was oxidized to the sulfonic acid with hydrogen peroxide (Scheme 8.8) [105]. Lanthanum metal was introduced by treating this moiety with lanthanum chloride and the chloride moiety of the resulting lanthanum sulfonate was exchanged with the triflate counterion on treatment with trifluoromethanesulfonic acid. 

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