• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.255-260
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• 2012

A new series of silaanthracenophanes 2-5 composed of 1,8-diethynylanthracene unit has been synthesized from silylation reactions of 1,8-di(lithioethynyl)anthracene with 1,3-dichloro-1,1,3,3-tetraalkyldisiloxanes and 1,2-dichlorotetramethyldisilane. The silaanthracenophane products 2-4 were characterized by spectroscopic methods and X-ray crystallographic analysis.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.171-173
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• 1987

Some pyridazin-6-one nucleosides have been prepared directly without silylation of heterocyclic base using iodine catalyst, a new type Friedel-Crafts catalyst.

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.769-772
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• 2002

• Mass Spectrometry Letters
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• v.3 no.1
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• pp.4-9
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• 2012

• YAKHAK HOEJI
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• v.23 no.1
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• pp.7-10
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• 1979

A gas chromatographic determination of dienestrol in dienestrol cream has been studied. Dienestrol cream was dissolved in pyridine and silylation was done by using N, O-bis (trimethylsilyl) trifluoroacetamide. The derivative was injected into 3% silicone OV-17 column for chromatographic estimation. The dienestrol peak was found to be well separated from the other components of the cream. The detection limit was obtained to be $5.6{\times}10^{11}$ mol of dienestrol for this method. As there is no need for prior separation procedure, this experiment is extremely simple and less time consuming as compared to the conventional methods for estimation of dienestrol in cream.

• YAKHAK HOEJI
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• v.27 no.4
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• pp.289-293
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• 1983

Twelve new N-piperoyl amino acids were synthesized by acylation of amino acids with piperoylchloride in order to develop the new central nervous depressants. Silylation of the carboxylic group of amino acids not only precluded side reactions but-also facilitated acylation at room temperature without catalysts. The acute toxicity of all the synthesized compounds were lower than that of piperine itself, whereas they showed strong protective effect against the strychnine-induced mortality.

• Korean Journal of Materials Research
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• v.22 no.6
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• pp.275-279
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• 2012

(3-mercaptopropyl)trimethoxysilane (MPTMS) was used as a silylation agent, and modified silica nanoparticles were prepared by solution polymerization. 2.0 g of silica nanoparticles, 150 ml of toluene, and 20 ml of MPTMS were put into a 300 ml flask, and these mixtures were dispersed with ultrasonic vibration for 60 min. 0.2 g of hydroquinone as an inhibitor and 1 to 2 drops of 2,6-dimethylpyridine as a catalyst were added into the mixture. The mixture was then stirred with a magnetic stirrer for 8 hrs. at room temperature. After the reaction, the mixture was centrifuged for 1 hr. at 6000rpm. After precipitation, 150 ml of ethanol was added, and ultrasonic vibration was applied for 30 min. After the ultrasonic vibration, centrifugation was carried out again for 1 hr. at 6000rpm. Organo-modification of silica nanoparticles with a ${\gamma}$-methacryloxypropyl functional group was successfully achieved by solution polymerization in the ethanol solution. The characteristics of the ${\gamma}$-mercaptopropyl modified silica nanoparticles (MPSN) were examined using X-ray photoelectron spectroscopy (XPS, THERMO VG SCIENTIFIC, MultiLab 2000), a laser scattering system (LSS, TOPCON Co., GLS-1000), Fourier transform infrared spectroscopy (FTIR, JASCO INTERNATIONL CO., FT/IR-4200), scanning electron microscopy (SEM, HITACHI, S-2400), an elemental analysis (EA, Elementar, Vario macro/micro) and a thermogravimetric analysis (TGA, Perkin Elmer, TGA 7, Pyris 1). From the analysis results, the content of the methacryloxypropyl group was 0.98 mmol/g and the conversion rate of acrylamide monomer was 93%. SEM analysis results showed that the organo-modification of ultra-fine particles effectively prevented their agglomeration and improved their dispensability.

• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.417-423
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• 2006

A series of amine functionalized MCM-41 catalysts were prepared by aminopropyltrimethoxysilane grafting and their catalytic performance in Knoevenagel reaction of selected substrates was investigated. Water resistant and catalytically active amine grafted MCM-41 was prepared by post-synthetic silylation using methyltrimethoxysilane ; hydrogen bonding of the water molecules formed during the condensation reaction to the active N group was suppressed, which led to high TON of the reaction. Amine functionalized MCM-41 prepared by coating method produced high conversion, but the TON of the catalyst was much lower than that of the amine grafted MCM-41; pore volume of the functionalized MCM-41 decreased substantially and large portion of the immobilized amine is believed to be hydrogen bonded to each other, which can result in decrease in the basicity of the N group. A secondary amine group was prepared by room temperature condensation between aminopropylsilane and chloropropylsilane, and the MCM-41 grafted with the secondary amine group demonstrated the highest catalytic activity among the catalysts prepared.

• Journal of Food Hygiene and Safety
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• v.10 no.3
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• pp.189-197
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• 1995

Analytical method for synephrine and octopamine in citrus fruits, drinks containing citrus fruit, and human urine was developed using gas chromatography / mass spectrometry(GC/MS), Silylation with MSTFA, acetylation with MBTFA, and trimethylsilylation with MSTFA followed by trifiuoroacetylation with MBTFA were compared. The selective derivatization of synephrine and octopamine was optimized with two derivatizing reagents ; MSTFA and MBTFA. The ion at m/z 267 was monitored to characterize the benzyl group of the both compounds. Synephrine was detected in the concentrations of 0.46∼1.88 ug/g for citrus fruits and 1.2∼8.1 ug/ml for drinks. The urinary excretion data of synephrine showed the highest concentration at the period of 8-20 hours after drinking orange juices and total amounts of its urinary excretion calculated as a parent compound was 11-14% of a dose during 48 hours. Octopamine was not detected in citrus fruits, drinks, and human urine.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.257-258
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• 2003

Crafting process consists of the reversible protection of the hydroxyl groups of the polysaccharide backbone by silylation, followed by the ring-opening polymerization (ROP) of $\varepsilon$-caprolactone (CL) initiated by the free remaining hydroxyl groups of the partially silylated dextran in the presence of tin-based catalysts. The last step relies upon the removal of silylating groups under mild acidic conditions yielding the desired amphiphilic graft copolymers.