Silica-Acetate Complex of N₂O₄: A Heterogeneous Reagent for the Selective Nitration of Phenols and Nitrosation of Thiols

Separation, preconcentration and determination of silver ion from water samples using silica gel modified with 2,4,6-trimorpholino-1,3,5-triazin

“…Using this methodology, the formation of side products makes a serious problem. Recently, an easy and efficient method was reported for the preparation of silica-based reagents [35][36][37]. This method was used for the preparation of morpholinated and 8-hydroxyquinolinated silica gels [38].…”

Palladium-Catalyzed Aromatic C–H Bond Nitration Using Removable Directing Groups: Regiospecific Synthesis of Substituted o-Nitrophenols from Related Phenols

“…However, this nitration strategy has several persistent problems that are hard to overcome: (1) poor regioselectivity, especially for monosubstituted arenes, e.g., toluene, phenol, etc. ; (2) poor chemoselectivity arising from over-nitrations (for example, the electrophilic nitrations of phenol sometimes give over-nitrated products as well besides mononitrated products); (3) limited functional group and/or substrate compatibility due to the use of strongly acidic and oxidative reagents (e.g., mixed H 2 SO 4 and HNO 3 ); and (4) difficult to achieve site-regiospecific nitration against the inherent orientation rules. For example, it is hard to realize regiospecific ortho -nitration of arenes substituted with meta -directing groups (e.g., aryl ketones, aldehydes, and acids etc.…”

Efficient preconcentration and determination of traces of aluminum ion using silica-bonded glycerol sorbent

“…An easy and efficient method for the preparation of silica-based reagents has been reported previously [29][30][31]. The preparation of directly bonded 2-mercaptobenzothiazole-silica gel and glycerolbonded silica gel has been reported in our previous works [32,33].…”