Al(H2PO4)3 as an efficient and reusable catalyst for the multi-component synthesis of highly functionalized piperidines and dihydro-2-oxypyrroles

Trifluoroacetic Acid Catalyzed One-Pot Four-Component Domino Reaction for the Synthesis of Substituted Dihydro 2-Oxypyrroles

“…Therefore, the development of a milder and more efficient route for one-pot synthesis of these important heterocycles is still in demand. In continue of our ongoing program on multi-component reactions [26][27][28][29][30][31], an efficient and convenient synthesis of N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates has been accomplished using trifluoroacetic acid as an efficient catalyst in MeOH at ambient temperature, with good yields (Schemes 1). Trifluoroacetic acid is widely utilized in organic synthesis as a solvent [32] or as an acid catalyst for different organic transformations such as rearrangements [33], functional group deprotections [34], reductions [35], oxidations [36], hydroarylations [37], condensations [38], and also trifluoromethylation reactions [39].…”

Nano-TiCl4/SiO2: an efficient catalyst for the one-pot synthesis of highly substituted dihydro-2-oxopyrroles

“…Recently, a few methods have been reported for the synthesis of dihydro-2-oxopyrroles via MCRs such as catalyst-free reaction of enaminones with N,N 0 -bis(phenylmethylidene) [28], catalyst-free/AcOH [29], and in the presence of I 2 [30], AcOH/NEt 3 [31], Cu(OAc) 2 [35], and InCl 3 [36]. Considering that, some of these procedures have drawbacks, such as high reaction temperature, long reaction times, and tedious work-up condition like utilizing column chromatography.…”

ZrCl4 as an efficient catalyst for one-pot four-component synthesis of polysubstituted dihydropyrrol-2-ones

“…As a part of our program aimed at developing a new procedure for the preparation of dihydropyrrol-2-ones [30][31][32][33][34][35], in this work, we report an efficient and very facile synthesis of polyfunctionalized dihydropyrrol-2-ones via one-pot fourcomponent reaction of amines, dialkyl acetylenedicarboxylates and formaldehyde in the presence of a catalytic amount of zirconium tetrachloride (ZrCl 4 ) in methanol at ambient temperature (Scheme 1).…”