Preparation and applications of fluoroalkyl end-capped vinyltrimethoxysilane oligomeric silica/chemically modified cellulose fibers composites

Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(CH2-CHSi(OMe)3) n-RF: n = 2, 3; RF = CF(CF3)OC3F7: RF-(VM) n-RF] was found to undergo the sol-gel reaction under alkaline conditions in the presence of chemically modified cellulose fibers treated with N-methylglucamine units ( MeGlu) [Cellu-fiber- MeGlu] and treated with iminodiacetic acid units ( ImDia) (Cellu-fiber- ImDia) to provide the corresponding fluorinated oligomeric silica/Cellu-fiber- MeGlu composites [RF-(VM-SiO3/2) n-RF/Cellu-fiber- MeGlu] and /Cellu-fiber- ImDia composites [RF-(VM-SiO3/2) n-RF/Cellu-fiber- ImDia], respectively. Dodecane and water contact angle measurements showed that these obtained composites can supply a superamphiphobic characteristic on their composite powders surface. The RF-(VM-SiO3/2) n-RF/Cellu-fiber- ImDia composites were applied to the packing material for the column chromatography to separate the mixture of hydrocarbon and fluorocarbon oils. In addition, the RF-(VM-SiO3/2) n-RF/Cellu-fiber- ImDia composites were found to have more effective removal ability for fluorinated aromatic compounds than that for the corresponding non-fluorinated ones from aqueous methanol solutions. Interestingly, it was demonstrated that the RF-(VM-SiO3/2) n-RF/Cellu-fiber- MeGlu composite powders are also applicable to the fabrication of liquid marbles, which are millimeter-sized liquids such as water, glycerine, ethylene glycol and dodecane stabilized by the adsorbed composite powders at air-liquid interfaces.

Synthesis and structure of rhodium(i) silyl carbonyl complexes: photochemical C–F and C–H bond activation of fluorinated aromatic compounds

Rhodium(i) silyl carbonyl complexes such as [Rh{Si(OEt)3}(CO)(dippe)] turned out to be a suitable precursor for the photochemical C–F and C–H bond activation of fluorinated aromatic compounds.

Synthesis of Fluorinated Aromatic Compounds by One-Pot Benzyne Generation and Nucleophilic Fluorination

The fluorination of substituted benzenes using fluoride ions under mild reaction conditions has been one of the most important challenges for the synthesis of biologically active fluorinated aromatic compounds; however, only a few synthetically useful methods are known. In this paper, it is reported that the nucleophilic fluorination of benzynes, generated from either 2-(trialkylsilyl)phenyl nonafluorobutanesulfonates or 2-(trialkylsilyl)phenols, meets this challenge. In particular, the fluorination starting from 2-(trialkylsilyl)phenols for fabricating aryl fluorides involves three sequential reactions in one-pot: the nonaflylation of phenols, benzyne generation, and nucleophilic fluorination of the benzynes. The regioselectivities of these reactions are controlled by the substituents at the C3-position of the benzynes.