• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1519-1524
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• 2008

We have investigated the photophysics of the acetone radical cation in the vacuum ultraviolet energy region by multiphoton ionization combined with time-of-flight mass spectrometry in a cluster beam. We have found that the loss of methyl radical from the acetone radical cations is remarkably suppressed at 10.5 eV when they are solvated by a few neutral acetone molecules. The cluster ion mass spectra obtained by nanosecond and picosecond laser pulses reveal that there are intermolecular processes, occurring in several tens of picoseconds, which are responsible for the survival of the acetone cations in clusters. This remarkable solvation effect on the yield of the methyl radical loss from the acetone cation can be rationalized by the intracluster vibrational energy redistribution and the self-catalyzed enolization which compete with the methyl radical loss process.

• Bulletin of the Korean Chemical Society
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• v.6 no.5
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• pp.284-287
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• 1985

Cyanoisopropyl radical derived from azobisisobutyronitrile (AIBN) by either thermolysis or photolysis reacts with oxygen to give cyanoisopropylperoxy radical which then was converted to acetone and cyano radical and/or acetyl cyanide and methyl radical. Of these products, acetone formed was quantitatively determined by the addition of thianthrene cation radical perchlorate to the reaction mixture. The results showed that 55.7 mmol, 16.9 mmol, and 16.0 mmol of acetone were formed for 7 hours from 1 mol of AIBN at $82{\pm}1^{\circ}C$ in acetonitrile, carbon tetrachloride, and benzene, respectively. However, 22.2 mmol of acetone was formed from photolysis of 1 mmol of AIBN in acetonitrile. The value decreased to 13.2 mmol by bubbling argon into the solvent prior to photolysis.

• Bulletin of the Korean Chemical Society
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• v.7 no.2
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• pp.150-153
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• 1986

Co-sensitized photooxygenation of 1,1-diphenyl-2-vinylcyclopropane (VCP-DPh) with 9,10-dicyanoanthracene and biphenyl in oxygen-saturated acetonitrile solution produced 3,3-diphenyl-5-vinyl-1,2-dioxolane as the major product. The same photoproduct was obtained by acetone sensitized photooxygenation in oxygen-saturated acetone solution. However, VCP-DPh remained intact when directly irradiated with DCA or irradiated with Rose Bengal to generate singlet oxygen. A mechanism involving a cosensitizer radical cation and sensitizer radical anion is proposed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.327-332
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• 2016

This study investigated the antioxidant and antimicrobial activities of various solvents (acetone, ethyl acetate, and ethanol) for extraction of Auricularia auricula-judae. Antioxidant activity was evaluated by determining total polyphenol and flavonoid contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging activity. Total polyphenol and flavonoid contents were not significantly different among the extracts, whereas DPPH radical scavenging activity and ABTS cation radical scavenging activity were significantly higher in ethanol and acetone extracts. DPPH radical scavenging activities of ethanol and acetone extracts showed high values (58.7% and 46.7%, respectively). The antimicrobial properties of these extracts were determined against six bacterial pathogens (Bacillus subtilis, Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aeruginosa, and Enterobacter cloacae) by the disc diffusion method. The acetone extracts showed antimicrobial activities against all tested bacteria, and all extracts showed the highest antimicrobial activity against B. subtilis.

• Bulletin of the Korean Chemical Society
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• v.6 no.6
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• pp.358-361
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• 1985

Thianthrene cation radical perchlorate (1) reacted with azo-bis-2-phenoxy-2-propane (6) to give thianthrene (2), cisthianthrene-5,10-dioxide, 5-(p-hydroxyphenyl) thianthrenium perchlorate (10), acetone, phenol, and 5-(2-propenyl) thianthrenium perchlorate (11) when the mole trtio of 1 to 6 was 1:1. Among the products, 11 was a new compound. However, when the corresponding mole ratio was 5:1, 11 was not formed. Similar result was obtained for azo-bis-2-(p-nitrophenoxy)-2-propane.

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.319-320
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• 2008

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.29-34
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• 2014

The aim of the study was to examine the cosmetic and biological activity of Lagerstroemia indica L. and it is possible that can be used as a cosmetic ingredient for application of cosmetic industries. Lagerstroemia indica L. branch was extracted with 70% acetone in water. In the result of DPPH (1,1-diphenyl-2-picryl-hydrazyl) scavenging radical activity, acetone extract of Lagerstroemia indica L. branch were higher than 73% at the 50 ppm concentration. ABTS radical cation decolorization activity by acetone extract were higher than 78% at the 50 ppm. Both examine of DPPH and ABTS showed high antioxidative activities at the 50 ppm. In the result of nitrite scavenging ability, acetone extract were higher than 63% at the 50 ppm. Collagenase inhibition activity by extract were higher than 85% at the 50 ppm. Extract is showed high collagenase inhibition more than comparison group EGCG at all concentration. These results suggest that Lagerstroemia indica L. has a great potential as a cosmeceutical raw material as well as anti-oxidant and anti-inflammatory and collagenase inhibition activity.

• Bulletin of the Korean Chemical Society
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• v.1 no.2
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• pp.49-54
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• 1980

Solutions of $Ni^{2+}$ and $Cd^{2+}$ were mixed with the solutions of various dibasic organic acids in the presence of cation exchange resin at room temperature. The distribution ratios of the metal ions between resin and solution were measured, using radioactive metal ions as tracer. From the observed variation of the distribution ratios with acid anion concentrations, it was concluded that $Ni^{2+}$ and $Cd^{2+}$ formed one-to-one complexes with succinate, malonate, o-phthalate and tartarate ions in aqueous, 20 % ethanol-water and 20 % acetone-water solutions. The results of the present study indicated that the relative stabilities of the complexes in solution increased generally in the order : $Ni^{2+}$ < $Cd^{2+}$ complexes. Succinate < malonate < o-phthalate < tartarate complexes. Aqueous < mixed solvent systems.

• Journal of Photoscience
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• v.7 no.4
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• pp.143-148
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• 2000

Studies have been conducted to explore single electron transfer(SET) promoted photocyclization of ($\omega$-phthalimidoalkoxy)acetic acids(alkoxy=ethoxy, n-propoxy and n-butyloxy). Photocyclizations occur in methanol or acetone in high yields to produce cyclized products in which phthalimide carbonyl carbon is bonded to the carbon of side chain in place of the carboxylic group. These photocyclizations are thought to proceed through pathways involving intramolecular SET from oxygen in the $\alpha$-carboxymethoxy groups to the singlet excited state phthalimide moieties followed by decarboxylation of the intermediate $\alpha$-carboxymethoxy cation fadicals and cyclizations by radical coupling. The photocyclizations occur ca. three times faster in both methanol or acetone with one equivalent of sodium hydroxide added to the reactions and occur slower in acetone than in methanol. The efficient and regiselective cyclization reactions observed for photolyses in methanol represent synthetically useful processes for construction of heterocyclic compounds.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.1
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• pp.35-39
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• 2016

In this research, we focused on the improvement of cy3 dye's characteristics for LCD color filter. Solubility and thermal stability are main characteristics of dyes for LCD color filter. We performed experiment to change counter cation of cy3 dyes with alkoxy substituent for these purposes. These cy3 dyes (1b~5b) were prepared through the synthetic procedure of three steps. The synthesized new cy3 dyes were charaterized by using NMR, FT-IR, UV/Vis spectroscopy, and TGA. These cy3 dyes showed purple color and maximum absorption wavelength (${\lambda}_{max}$) in the range of 578~590 nm in UV/Vis spectrum. We confirmed that solubility and thermal stability of cy3 dyes were dependent on the structure of counter cation. Cy3 dyes with alkoxy substituent have good solubility in organic solvents such as dichloromethane, methanol, and acetone. Especially, Cy3 dye with 4-nitrobenzyl counter cation (5b) gave excellent solubility characteristics.