• Journal of Photoscience
• /
• v.2 no.2
• /
• pp.77-81
• /
• 1995

Photoreactions of pseudosaccharin ethers have been investigated. Pseudosaccharin 3-allyl ether undergoes a facile photoreaction via reaction pathways involving homolysis of bond between pseudosaccharyl oxygen and 3-allyl carbon, and excited nucleophilic substitution of allyloxy group by solvent which are not quenched by oxygen present in the reaction. Product yield demonstrates that the homolysis pathway predominates over the nucleophilic substitution in ca. 7:1 ratio. In contrast, pseudosaccharin alkyl ethers follow different reaction routes to produce two products, solvent-substituted pseudosaccharin alkyl ethers and reduction products, 3-alkoxy-1, 2-benzisothiazoles. The formations of reduction products, 3-alkoxy-1, 2-benzisothiazoles are completely quenched by oxygen.

• Bulletin of the Korean Chemical Society
• /
• v.25 no.8
• /
• pp.1182-1188
• /
• 2004

Polydisperse oligo(PO-b-EO) allyl ether siloxane surfactants were synthesized by the hydrosilylation reaction of OMTS with Allyl-oligo(PO-b-EO) series. The surface tension of siloxane surfactants increased with increasing the EO chain length while it decreased with increasing the PO ratio. However, the sedimentation time of the aqueous solution showed opposite trend to the surface tension data. Both the surface tension and sedimentation time of the aqueous solution containing inorganic electrolyte gradually decreased as the content of inorganic electrolyte increased because of the surface arrangement of surfactant molecules. However, they increased with an increase of pH values due to the hydrolysis of the siloxane backbone. The $C_p$ values tended to increase with the increase in the EO chain length and decrease of the PO ratio. It seems that intermolecular interaction between PO/EO block copolymer and water affects the variation of transition temperature.

• Archives of Pharmacal Research
• /
• v.26 no.9
• /
• pp.667-678
• /
• 2003

We examined the effect of p-substituents in p-substituted cinnamyl methyl ethers and 1-(p-substituted phenyl)allyl methyl ethers with CSI, and confirmed that the CSI reaction of allyl ethers (p-substituted ethers) is a competitive reaction of $S_Ni{\;}and{\;}S_N1$ mechanism according to the stability of the carbocation. And, the only terminal allylic amine was obtained through the migration reaction in thermodynamic reaction condition.

• Journal of the Korean Applied Science and Technology
• /
• v.24 no.2
• /
• pp.160-166
• /
• 2007

The rheological properties and surface tensions of polymer solutions and polymer-surfactant mixed solutions were investigated. The polymers used in this study were a homopolymer of acrylic acid crosslinked with an allyl ether of pentaerythritol, an allyl ether of sucrose, or an allyl ether of propylene (CARBOMER), acylate/C10-30 alkyl acylate crosspolymer (AAAC), and ammonium acryloydimethyltaurate/VP copolymer (ADTV). A solubilizing agent PEG-40 hydrogenated castor oil (HCO-40) and an emulsifying agent polyoxyethylene (20) sorbitan monostearate (POLYSORBATE 60) made the micelles intervening between AAAC polymers, resulting in the increase of viscosity. However, HCO-40 made this behavior over the wider range of surfactant concentration than POLYSORBATE 60. From the view point of surface tensions in the same range of surfactant concentration, AAAC/HCO-40 solution showed the area of increasing surface tension with surfactant concentration in contrast to the AAAC/POLYSORBATE 60 solution showing no increasing area.

• Korean Journal of Food Science and Technology
• /
• v.25 no.6
• /
• pp.593-595
• /
• 1993

The volatile components of garlic extracts were investigated. For experiment both crushed- and sliced-garlic were dried by air-drying and freeze-drying methods, followed by ether extraction. The extracts were analysed by GC and GC/MS. Sliced- and freeze-dried garlic extracts showed larger number of volatile components than crushed- and air-dried garlic extracts. The volatile components, allyl propyl disulifde, 2-vinyl-1,3-dithiane, 3-vinyl-〔4H〕-1,2-dithiin, 1,2-Bis (allyl)disulfane were found in sliced- and freeze-dried garlic extracts, methyl allyl trisulfide and 2,4-methyl furane in sliced- and air-dried garlic extracts, and disulfide in crushed- and air-dried garlic extracts.

• Journal of the Korean Applied Science and Technology
• /
• v.34 no.2
• /
• pp.203-209
• /
• 2017

The propenyl ether-type monomers which are applicable for cationic photo-polymerization were synthesized by the condensation reaction of mono and di-functional alcohol with allyl bromide. To examine photo-curable reactivity, these monomers were combined with cationic photoinitiator to prepare coating composition. As a result, the initial rate of polymerization of POMB in mono propenyl ether type was 10.2, which was relatively lower than BPOB in di-propenyl ethers type. However, POMB containing 1.5mol% photoinitiator almost quantitatively reacted within 90 seconds. In addition, Sulfonium salt type photo-initiators containing long-alkyl group showed good solubility with monomers and apperaed to have comparatively higher rate of polymerization and conversion ratio when applying DPSA and DPST which have high acidity on all monomers.

• Bulletin of the Korean Chemical Society
• /
• v.5 no.6
• /
• pp.264-265
• /
• 1984

• Korean Chemical Engineering Research
• /
• v.48 no.5
• /
• pp.621-626
• /
• 2010

In this study, imidazole-based ionic liquid on polystyrene was prepared and its catalytic performance in the cycloaddition of $CO_2$ with allyl glycidyl ether(AGE) to produce allyl glycidyl carbonate was investigated. The ionic liquid was generated on the polystyrene-based polymer through the immobilization of imidazole. The prepared catalyst was characterized using a number of instrumental analysis including EA, FT-IR, TGA and SEM. The immobilized ionic liquid showed very good catalytic activity for the cycloaddition of $CO_2$ with AGE, having 80% of AGE conversion with over 96% of the carbonate selectivity at $120^{\circ}C$ under 1.48 MPa $CO_2$ pressure. The immobilized ionic liquid can be used for the reaction up to four consecutive runs without significant loss of its catalytic activity.

• Journal of Integrative Natural Science
• /
• v.13 no.2
• /
• pp.41-46
• /
• 2020

A study is reported about the synthesis processes of various silacrown ether by the reaction of alkoxysilanes with polyethylene glycols (PEG) through transesterification. Crown ether-functionalized carbosilane dendrimers and hybrid crown ethers are also discussed. We will also address the solubility enhancement, phase-transfer catalysis of different silacrown as well as their application as Ion-selective electrodes (ISEs) and as active phase of PVC electrodes for the development of potentiometric sensors for detection of alkali-Ions.

• Applied Biological Chemistry
• /
• v.40 no.5
• /
• pp.451-454
• /
• 1997

An attempt was made in this study to analyze volatile flavor components of fresh and odorless garlic (Allium sativum L.), Essential oils in fresh garlic and odorless garlic were isolated by a simultaneous steam distillation and extraction(SDE) method using n-pentane/diethy ether as solvent. A total of 21 and 22 components were identified by GC/MS from the essential oils of fresh garlic and odorless garlic, respectively. Diallyl trisulfide, diallyl disulfide and methyl allyl disulfide were found to be major volatile flavor components in fresh garlic and odorless garlic. By the preparation of ordorless garlic, 77.5% of diallyl trisulfide, 15.0% of diallyl disulfde, 72% of methyl allyl disulfide, and 78.4% of allyl thiol components in fresh garlic were lost. Eleven compounds including 2-vinyl-4H-1,3-dithiin, eugenol and 2-methoxy-4-vinyl-phenol were identified in odorless garlic, but not m fresh garlic.