Nano TiO2 as a heterogeneous catalyst in an efficient one-pot three-component Mannich synthesis of β-aminocarbonyls

Rutile phase nanoTiO2 as an effective heterogeneous catalyst for condensation reaction of isatin derivatives with 1,2-diaminobenzene under solvent free conditions: A greener “NOSE” approach

“…TiO 2 nanoparticle catalyst as an inexpensive, non-toxic, moisture stable, reusable, commercially available white powder is of great interest to many scientists in the recent years. In general, several similar applications of this nanoscale method, as an effective catalyst in green synthetic organic chemistry, have already been highlighted in the literature (Abdolmohammadi, 2012;Hosseini-Sarvari, 2007;Kassaee et al, 2011;Lakshmi Kantam et al, 2006;RoperoVega et al, 2010;Shirini et al, 2011).…”

Application of Nanocatalysts in Multi-Component Reactions

“…The catalyst was easily separated from the reaction mixture and reused four times with no significant loss of its catalytic activity (Scheme 43). 57 Xanthene and its derivatives are known as an important class of heterocyclic compounds widely used as leucodye, pH-sensitive fluorescent materials for visualization of biomolecules and utilized in laser technologies due to their photochemical and photo physical properties. They have been reported to possess diverse biological and therapeutic properties such as antibacterial, antiviral, anti-proliferative and anti-inflammatory activities.…”

One Pot Synthesis of Multiaryl-Substitutedβ-Amino Ketone Compo- unds Catalyzed by Silica-Supported Rare Earth Terbium Chloride

“…Lewis 酸 [2～4] , Brønsted 酸 [5] , Ps-SO 3 H [6] , 氨基磺酸 [7] , 离 子液体酸 [8] 和杂多酸 [9] 等, 这类酸催化剂存在催化产率 低、催化反应时间长、催化反应步骤繁琐、污染环境和 对设备腐蚀等问题; 另一类是各种盐类或氧化物催化 剂, 像过渡金属盐 [10] , 稀土金属盐 [11] , 吡啶三氟醋酸 盐 [12] , Fe(Cp) 2 PF 6 [13] , NaBAr 4 F [14] , Yb(OTf) 3 [15] , Re-(PFO) 3 [16] , Re(OPf) 3 [17] , Nano TiO 2 [18] 等, 这类催化剂虽 然表现出很好的催化性能, 但存在分离困难、催化剂用 量大、催化产率低、污染环境以及催化剂难以回收利用 等问题. 近几年, 对支载、负载型催化剂研究越来越受重视, 文 献 报 道 , SiO 2 -OAlCl 2 [19] , H 2 SO 4 -SiO 2 [20] 和 HClO 4 -SiO 2 [21] 等已经作为一种新型催化剂应用到合成 β-氨基 …”