- Cationic ring-opening polymerization of five-membered cyclic thiocarbonate bearing an adamantane moiety via selective ring-opening direction
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A novel five-membered cyclic thiocarbonate bearing adamantane moiety, 4,6-dioxatetracyclo-[6.3.1.1.3,10O3,7]tridecane-5-thio (1), was synthesized from 1,2-adamantanediol and thiophosgene in the presence of pyridine. Monomer 1 underwent cationic ring-opening polymerization initiated by triethyl-oxonium tetrafluoroborate (Et3OBF4), methyl trifluoromethanesulfonate (TfOMe), trifluoromethanesulfonic acid (TfOH), and H2O with 2 mol% of boron trifluoride etherate (BF3OEt2) in CH2Cl2 at 30° to afford the polythiocarbonate by isomerization of the thiocarbonyl group into a carbonyl group with selective ring-opening direction. The number-average molecular weight and polydispersity of the polymer obtained by polymerization with H2O/BF3OEt2 were 10 600 and 1.44, respectively. The temperature with 5% weight loss of the obtained polymer was 338°C. Monomer 1 expanded as large as 14% during the polymerization.
- Kameshima, Hisamitsu,Nemoto, Nobukatsu,Sanda, Fumio,Endo, Takeshi
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- Binuclear iron(III) phthalocyanine(μ-oxodimer)/tetrabutylammonium oxone: A powerful catalytic system for oxidation of hydrocarbons in organic solution
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Binuclear iron(III) phthalocyanine-(μ-oxodimer) complex was tested in catalytic oxygenation reactions of several hydrocarbons using tetrabutylammonium oxone as the oxidant in dichloromethane solution at room temperature. Results of the study demonstrate that this is an extremely powerful catalytic system for oxidative conversion of aromatic hydrocarbons (anthracene, 2-tert- butylanthracene, 2-methylnaphthalene, 9, 10-dihydroanthracene, 1,2,3,4-tetrahydronaphthalene, indane, ethylbenzene, toluene, and benzene) to the respective p-quinones in high yields in 5-30 min. Under these conditions, adamantane is oxidized with 71% conversion after 10 min affording a mixture of 1 -adamantanol, 2-adamantanone, 1-hydroxy-2-adamantanone, and 4-protoadamantanone.
- Neu, Heather M.,Zhdankin, Viktor V.,Nemykin, Victor N.
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scheme or table
p. 6545 - 6548
(2011/02/22)
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- Lewis-acid Catalysed Oxidation of Alkanes by Chromate and Permanganate
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The oxidation of alkanes by chromate and permanganate has been found to be greatly accelerated by Lewis acids such as BF3 and AlCl3; reaction occurs within minutes at room temperature in the presence of just a few equivalents of the Lewis acids.
- Lau, Tai-Chu,Wu, Zhi-Biao,Bai, Zi-Long,Mak, Chi-Keung
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p. 695 - 696
(2007/10/02)
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