Metal-based Lewis acid catalysts for conversion of a variety of aldehydes with acetic anhydride to gem 1,1-diacetates

NbCl5 Functionalized Perlite: A Potent and Recyclable Catalyst for Synthesis of Pyrans

“…Currently, Lewis acid-based heterogeneous catalysts are popular due to their innoxious and economic nature, and their compelling ability to proceed the heterocyclic compound synthesis [11][12][13][14]. The Lewis acids are known to be a better candidate for incorporation into a solid support; they have excellent polarisability and a good coordinating capacity [15].…”

Chemo-Selective Protection of Aldehydes Functional Group Catalyzed by MOFs

“…The characteristic of stability in neutral environments, the comfort of preparation, and multiple applications, including as initiating materials for the Diels-Alder reaction, intermediates in industrial processes, and geminal diacetates (acylals), have been highlighted among the various protection approaches of aldehydes [2,3]. Ethanethiol, acetic anhydride, and alcohol are some of the reagents used to protect aldehydes [4]. The use of protic or Lewis acid catalysts such as AC-N-SO 4 H [5], magnetic Fe 3 O 4 @C-600-SO 3 H microspheres [6], SiO 2 -NaHSO 4 [7], STO/Al-P [8], poly(p-hydroxybenzaldehyde-co-p-phenol sulfonate) [9], tungstosulfonic acid (TSA) [3], hexabromoacetone (HBA) [1], (MNPs-PSA) [2], and 5,10,15,20-tetrakis(pentafluorphenylporphyrin) iron (III) chloride (Fe 5 F) [10] play an essential role in the better progress of the chemo-selective reactions.…”

“…The use of protic or Lewis acid catalysts such as AC-N-SO 4 H [5], magnetic Fe 3 O 4 @C-600-SO 3 H microspheres [6], SiO 2 -NaHSO 4 [7], STO/Al-P [8], poly(p-hydroxybenzaldehyde-co-p-phenol sulfonate) [9], tungstosulfonic acid (TSA) [3], hexabromoacetone (HBA) [1], (MNPs-PSA) [2], and 5,10,15,20-tetrakis(pentafluorphenylporphyrin) iron (III) chloride (Fe 5 F) [10] play an essential role in the better progress of the chemo-selective reactions. Heterogeneous acid catalysts have advantages over their homogeneous types, such as simple separation via straightforward filtration, possible reuse, and convenient provision, which make them an ideal choice for catalyzing synthesis reactions [4]. Metal-organic frameworks (MOFs) are a new type of hybrid material composed of metal nodes and organic ligands [11,12].…”

Sodium toluene‐4‐sulfonate as a reusable and ecofriendly catalyst for greener synthesis of 5‐aminopyrazole‐4‐carbonitrile in aqueous medium

“…[ 29–32 ] Synthesis of heterocyclic scaffolds is performed via MCRs in the presence of various green tools and catalyst gives good results. [ 33–38 ]…”