• Journal of environmental and Sanitary engineering
• /
• v.13 no.1
• /
• pp.69-81
• /
• 1998

The reactivity increase of unsunstituted energetic compound in cyclic ethers was found in order of three-membered cyclic form < five-membered cyclic form< four-membered cyclic form. The nucleophilicity and basicity of cyclic ethers can be explained by the negative charge on oxygen atom of cyclic ethers. The reactivity of propagation in the polymerization of cyclic ethers can be represented by positive charge on carbon atom and the LUMO energy of active species of cyclic ethers. The cationic polymerization of substituted cyclic ethers which have pendant energetic groups such as methoxy($-CH_{2}OCH_{3}$), azido($-CH_{2}N_{3}$), and nitrato($-CH_{2}ONO_{2}$) are investigated theoretically using the MNDO methods.

• Journal of Environmental Science International
• /
• v.17 no.3
• /
• pp.343-350
• /
• 2008

The fate of two cyclic ethers, THF(Tetrahydrofuran) and 1,4-Dioxane, in conventional biological wastewater treatment plants was investigated using sequential activated sludge process. Removal efficiency of THF were about 86% in average, which was greater than that of 1,4-Dioxane, 30%. However, it was not clear whether the removal of cyclic ethers in biological system was caused by microbial activity or not. Thus treatability tests were conducted by batch experiments. The effects of mixing, aeration and the addition of activated sludge on the removal of cyclic ethers were investigated in batch experiments. THF was totally removed by mixing and aeration in 24 hours while removal ratio of 1,4-Dioxane was at most 30% for the same period. This results could be ascribed to the differences in Henry's law constants between the two chemicals. In addition, biological degradation including biosorption was not obviously observed in these batch tests.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.4
• /
• pp.537-538
• /
• 2002

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.183.1-183.1
• /
• 2003

The synthesis of various cyclic carbamate compounds and amino alcohols has attracted attention in the past because of their potential as antibiotics, antitumor, analgenics, anticonvulsants. Several methods for the preparation of cyclic carbamate compounds have previously been reported including the use of heterocumulenes. We have recently described the novel synthetic method for N-protected amines from various ethers using Chlorosulfonyl isocyanate(CSI) and found that the mechanism of our CSI reaction is a competitive reaction of $S_N1$ and $S_ Ni$ mechanisms according to the stability of carbocation intermediates. (omitted)

• Bulletin of the Korean Chemical Society
• /
• v.17 no.1
• /
• pp.87-90
• /
• 1996

• Bulletin of the Korean Chemical Society
• /
• v.18 no.12
• /
• pp.1245-1247
• /
• 1997

• Bulletin of the Korean Chemical Society
• /
• v.28 no.4
• /
• pp.629-634
• /
• 2007

Photochemical reactions of N-methylphthalimide with silyl enol ethers have been explored. Irradiations of phthalimide (1) and cyclic silyl enol ethers (5a-b) are observed to promote formation of photoreduced phthalimides and photoaddition products by sequential SET-desilylation pathways. The photoreaction of phthalimide (1) and acyclic silyl enol ethers (5c-d) leads to produce oxetanes which arise by competitive single electron transfer (SET) and classical 2+2 photocycloaddition (Parteno-Buchi reaction) pathways.

• Bulletin of the Korean Chemical Society
• /
• v.25 no.10
• /
• pp.1465-1470
• /
• 2004

A short and efficient synthesis, solvent extraction and potentiometric measurements of new thiazole-containing naphtho-crown ethers are reported. The naphthalene moiety enhances the ammonium ion selectivity over potassium ion. The selectivity of ${NH_4}^+/K^+$ follows the trend $3\;{\approx}\;2\;>\;1$, indicating that the differences in conformational changes of 2 and 3 in forming ammonium complexes affect little on the resulting ammonium/potassium extraction selectivity ratio. The ammonium ion-selective electrodes were prepared with noctylphenyl ether plasticized poly(vinyl chloride) membranes containing 1-4 the effect of one naphthalene unit introduced on either right (2) or left (3) side of thiazolo-crown ether on their potentiometric properties (e.g., ammonium ion selectivity over other cations, response slopes, and detection limits) were not apparent. However, the ammonium ion selectivity of 1, 2 and 3 over other alkali metal and alkaline earth metal cations is 10-100 times higher than that of nonactin.

• Bulletin of the Korean Chemical Society
• /
• v.26 no.2
• /
• pp.265-267
• /
• 2005

An efficient method of addition of trimethylsilyl cyanide to aldehydes by employing a zirconium complex as the catalyst has been described. A variety of aromatic, aliphatic, cyclic and heterocyclic aldehydes has been converted into corresponding trimethylsilyl ethers in excellent yield within short reaction time.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.12
• /
• pp.3509-3510
• /
• 2010