Synthesis and characterization of triflic acid-functionalized mesoporous Zr-TMS catalysts: heterogenization of CF3SO3H over Zr-TMS and its catalytic activity

Ordered organo-inorganic hybrid mesoporous solid acid catalysts (Zr–TMS–TFA) for Michael addition of indoles with α,β-unsaturated carbonyl compounds under environmentally benign solvent free conditions

“…The synthesis of ordered Zr-TMS (sample A), Zr-TMS-TFA (samples B through G) and amorphous Zr-TMS-TFA (sample H) catalysts were synthesized by known procedure [59] and described in detail in our recent publication [55], and hence not described here.…”

“…Recently, Singh and co-workers [59][60][61][62] reported various sulfonic acid functionalized Zr-TMS catalysts for various reaction like acetalization of ethyl acetoacetate, benzoylation of biphenyl, condensation of aniline benzoylation of diphenyl ether, etc. Sulphated zirconia catalyzes various industrially important reactions such as isomerization, condensation and Friedel-Craft acylation reaction [63].…”

Organosilanesulfonic acid-functionalized Zr-TMS catalysts: Synthesis, characterization and catalytic applications in condensation reactions

“…Further catalytic efficiency can easily be tuned either by doping the metal oxide with metals and/or other metal oxides or by functionalizing with organic species through active OH groups [6,7]. Singh and co-workers reported trifluoromethanesulfonic acid-and benzylsulfonic acid-functionalized Zr-TMS as efficient acid catalysts for the acylation, acetalization and condensation reactions of bulky molecules [8,9].…”

Superacid‐Catalyzed Reactions

“…Recently, acyl trifluoroacetates in excess triflic acid have been shown to be even more effective reagents 355 Amorphous and mesostructured ZrO 2 solid catalysts impregnated with various amounts of triflic acid were tested in the acylation of biphenyl 356,357 and toluene 358 (with benzoyl chloride and para-toluyl chloride, respectively, nitrobenzene solvent, 170 C and 130 C). Recently, acyl trifluoroacetates in excess triflic acid have been shown to be even more effective reagents 355 Amorphous and mesostructured ZrO 2 solid catalysts impregnated with various amounts of triflic acid were tested in the acylation of biphenyl 356,357 and toluene 358 (with benzoyl chloride and para-toluyl chloride, respectively, nitrobenzene solvent, 170 C and 130 C).…”