Scandium(III) Perfluorooctanesulfonate [Sc(OPf)3] : A Novel Catalyst for the Hetero Diels–Alder Reaction of Aldehydes with Non-Activated Dienes

Abstract

Scandium(III) perfluorooctanesulfonate [scandium(III) perflate, Sc(OPf)3] was prepared from either scandium(III) chloride or oxide and perfluorooctanesulfonic acid. The perflate thus obtained acts as a novel Lewis acid catalyst for the intermolecular hetero Diels–Alder reaction of aldehydes with non-activated dienes under mild conditions. The characteristic features of the catalyst include (i) low hygroscopicity, (ii) ease of handling, and (iii) robustness for the recycling use.

Rare earth(III) perfluorooctanesulfonates catalyzed Friedel–Crafts alkylation in fluorous biphase system

“…For example, in the Yb(OSO 2 C 8 F 17 ) 3 catalyzed reaction of anisole with benzyl alcohol in perfluorodecalin (C 10 F 18 , cis and trans-mixture), the yields of alkylation from the first run to the fifth run are 96, 94, 95, 94 and 92%, respectively. This may partly be attributed to the water-repellent nature of the perfluoroalkane chain ''(ÀCF 2 ÀCF 2 À) n '' of RE(OSO 2 C 8 F 17 ) 3 which refuses the approach of water molecules to the central metal cation, thus maintaining its high Lewis acidity [2].…”

“…However, the large-scale synthesis, involving more than stoichiometrical amount of Lewis acids such as aluminum trichloride (AlCl 3 ), makes alkylation one of the most environmentally harmful processes. Recently, many papers related with the Lewis acids of rare earth(III) perfluorooctane sulfonates (RE(OSO 2 C 8 F 17 ) 3 ) have been published [1][2][3][4]. The characteristic features of the catalyst include low hygroscopicity, ease of handling, robustness for the recycling using and high solubility in fluorous solvent [2][3][4].…”

“…Recently, many papers related with the Lewis acids of rare earth(III) perfluorooctane sulfonates (RE(OSO 2 C 8 F 17 ) 3 ) have been published [1][2][3][4]. The characteristic features of the catalyst include low hygroscopicity, ease of handling, robustness for the recycling using and high solubility in fluorous solvent [2][3][4]. Shi and Cui reported in 2002 that RE(OSO 2 C 8 F 17 ) 3 could catalyze Friedel-Crafts acylation effectively [4].…”

“…RE(OSO 2 C 8 F 17 )3 was prepared according to the literatures[2] (Method A). The mixture of C 8 F 17 SO 3 H solution (aq) and YbCl 3 Á6H 2 O solution (aq) was stirred at room temperature (Method B).…”

Heterogeneous catalysis of novel polymeric rare earth complexes under solvent-free conditions: Zero-emission synthesis of β-amino alcohols

“…The catalytic activity of RE 2 (BPDS) 3 as well as Sc(OPf) 3 (Pf = SO 2 C 8 F 17 ), which was previously prepared in this laboratory [23], was tested for the ring-opening reaction of cyclohexene oxide with benzylamine. When the reactions were carried out by using 2.5 mol% of Sc(OPf) 3 or 5 mol% of Sc 2 (BPDS) 3 in toluene at room temperature under heterogeneous conditions, the desired amino alcohol was obtained in only low yield, respectively (Table 1, entries 1 and 2).…”