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Carbon dioxide compounds compound structure

EXAMPLE 11.11 When the peroxide with structure 11-6 is heated in the presence of iodine, four major products are formed carbon dioxide and compounds 11-7,11-8, and 11-9. When the reaction is monitored by H NMR, the signal for 11-7 (5 2.1) exhibits a strong A net effect, while the signal for 11-9 (5 2.7) shows a strong E net effect ... [Pg.186]

The first report on DFA formation in higher plants dates back to 1933, when Schlubach and Knoop [23] isolated a compound tentatively identified as a-D-fructofuranose p-o-fmctofuranose l,2 2,l -dianhydride (10, also known as DFA I) from Jerusalem artichoke. Alliuminoside, a difructofuranose 2,6 6,2 -dianhydride for which configuration at the glycosidic linkages was not determined, was isolated from tubers of Allium sewertzowi [24], However, the fact that these results have not been further confirmed throws some doubt onto whether the DFAs were actually from plant origin or were formed by the presence of microorganisms. The enzymic formation of a-o-fructofuranose p-o-fructofuranose l,2 2,3 -dianhydride (1, DFA HI) in sterilized homogenates of the roots of Lycoris radiata, a plant use in China as a traditional folk medicine, unequivocally demonstrated the capacity of this plant to produce this particular DFA [25]. The compound was further extracted from the intact bulbs by supercritical carbon dioxide and its structure unequivocally established by NMR [26]. [Pg.52]

Why is potassium aluminium sulphate not soluble in benzene A compound M has the composition C = 50.0% H=12.5%o A1 = 37.5%. 0.360 g of M reacts with an excess of water to evolve 0.336 1 of gas N and leave a white gelatinous precipitate R. R dissolves in aqueous sodium hydroxide and in hydrochloric acid. 20 cm of N require 40 cm of oxygen for complete combustion, carbon dioxide and water being the only products. Identify compounds N and R, suggest a structural formula for M, and write an equation for the reaction of M with water. (All gas volumes were measured at s.t.p.)... [Pg.159]

When levuhnic acid (CH3CCH2CH2CO2H) was hydrogenated at high pressure over a nickel catalyst at 220°C a single product C5Hg02 was isolated in 94% yield This compound lacks hydroxyl absorption in its IR spectrum and does not immediately liberate carbon dioxide on being shaken with sodium bicarbonate What is a reasonable structure for the compound" ... [Pg.828]

By far the majority of the million or so known compounds of carbon also contain hydrogen and oxygen. There are several important types of oxygen-containing organic compounds and they can be studied as an oxidation series. For instance, the compound methanol, CH3OH, is very closely related to methane, as their structural formulas show. Methanol can be regarded as the first step in the complete oxidation of methane to carbon dioxide and water. [Pg.332]

Land/atmospheric interfacial processes which impact climate and biological activity on earth are illustrated in Figure 3. Emissions of carbon dioxide, methane, nitrogen dioxide, and chlorofluorocarbons (CFCs) have been linked to the transmission of solar radiation to the surface of the earth as well as to the transmission of terrestrial radiation to space. Should solar radiation be an internal process or an external driver of the hydrologic cycle, weather, and air surface temperatures Compounds of sulfur and nitrogen are associated with acidic precipitation and damage to vegetation, aquatic life, and physical structures. [Pg.11]

Cobalt(II) alkoxides are known and monomeric forms are part of a wider review.413 The interest in these compounds pertains to a potential role in catalysis. For example, a discrete cobalt(II) alkoxide is believed to form in situ from a chloro precursor during reaction and performs the catalytic role in the decomposition of dialkyl pyrocarbonates to dialkyl carbonates and carbon dioxide.414 A number of mononuclear alkoxide complexes of cobalt(II) have been characterized by crystal structures, as exemplified by [CoCl(OC(t-Bu)3)2 Li(THF)].415 The Co ion in this structure and close relatives has a rare distorted trigonal-planar coordination geometry due to the extreme steric crowding around the metal. [Pg.44]

CO3 species was formed and the X-ray structure solved. It is thought that the carbonate species forms on reaction with water, which was problematic in the selected strategy, as water was produced in the formation of the dialkyl carbonates. Other problems included compound solubility and the stability of the monoalkyl carbonate complex. Van Eldik and co-workers also carried out a detailed kinetic study of the hydration of carbon dioxide and the dehydration of bicarbonate both in the presence and absence of the zinc complex of 1,5,9-triazacyclododecane (12[ane]N3). The zinc hydroxo form is shown to catalyze the hydration reaction and only the aquo complex catalyzes the dehydration of bicarbonate. Kinetic data including second order rate constants were discussed in reference to other model systems and the enzyme carbonic anhy-drase.459 The zinc complex of the tetraamine 1,4,7,10-tetraazacyclododecane (cyclen) was also studied as a catalyst for these reactions in aqueous solution and comparison of activity suggests formation of a bidentate bicarbonate intermediate inhibits the catalytic activity. Van Eldik concludes that a unidentate bicarbonate intermediate is most likely to the active species in the enzyme carbonic anhydrase.460... [Pg.1185]


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