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Spectroscopy alcohols

The varying actual orientation of molecules adsorbed at an aqueous solution-CCU interface with decreasing A has been followed by resonance Raman spectroscopy using polarized light [130]. The effect of pressure has been studied for fatty alcohols at the water-hexane [131] and water-paraffin oil [132] interfaces. [Pg.85]

Deuterium does not give a signal under the conditions of H NMR spectroscopy Thus replacement of a hydroxyl proton by deuterium leads to the disappearance of the OH peak of the alcohol Protons bonded to nitrogen and sulfur also undergo exchange with... [Pg.544]

ALCOHOLS,HIGHERALIPHATIC - SURVEY AND NATURALALCOHOLSMANUFACTURE] (Voll) -analysis using Raman spectroscopy [SPECTROSCOPY, OPTICAL] (Vol 22)... [Pg.743]

However, a second mole of alcohol or hemiformal caimot be added at the ordinary pH of such solutions. The equiUbrium constant for hemiformal formation depends on the nature of the R group of the alcohol. Using nmr spectroscopy, a group of alcohols including phenol has been examined in solution with formaldehyde (15,16). The spectra indicated the degree of hemiformal formation in the order of >methanol > benzyl alcohol >phenol. Hemiformal formation provides the mechanism of stabilization methanol is much more effective than phenol in this regard. [Pg.293]

The poly(vinyl alcohol) made for commercial acetalization processes is atactic and a mixture of cis- and /n j -l,3-dioxane stereoisomers is formed during acetalization. The precise cis/trans ratio depends strongly on process kinetics (16,17) and small quantities of other system components (23). During formylation of poly(vinyl alcohol), for example, i j -acetalization is more rapid than /ra/ j -acetalization (24). In addition, the rate of hydrolysis of the trans-2iQ. -A is faster than for the <7 -acetal (25). Because hydrolysis competes with acetalization during acetal synthesis, a high cis/trans ratio is favored. The stereochemistry of PVF and PVB resins has been studied by proton and carbon nmr spectroscopy (26—29). [Pg.450]

Infrared Spectroscopy (ir). Infrared curves are used to identify the chemical functionality of waxes. Petroleum waxes with only hydrocarbon functionality show slight differences based on crystallinity, while vegetable and insect waxes contain hydrocarbons, carboxyflc acids, alcohols, and esters. The ir curves are typically used in combination with other analytical methods such as dsc or gc/gpc to characterize waxes. [Pg.318]

Phenethyl alcohol may be identified as the phenethyl -nitrobenzoate [57455-00-2] (mp 106—108°C), as phenethyl -nitrobenzyl phthalate [65997-34-4] (mp 84.3°C), and also by its formation of styrene on treatment with alkaU. Use of these derivatives has, however, been superseded by physical methods. Infrared (75,76), mass spectroscopy (77), and nmr spectra (78) are useful for identification. [Pg.61]

An unusual method for the preparation of syndiotactic polybutadiene was reported by The Goodyear Tire Rubber Co. (43) a preformed cobalt-type catalyst prepared under anhydrous conditions was found to polymerize 1,3-butadiene in an emulsion-type recipe to give syndiotactic polybutadienes of various melting points (120—190°C). These polymers were characterized by infrared spectroscopy and nuclear magnetic resonance (44—46). Both the Ube Industries catalyst mentioned previously and the Goodyear catalyst were further modified to control the molecular weight and melting point of syndio-polybutadiene by the addition of various modifiers such as alcohols, nitriles, aldehydes, ketones, ethers, and cyano compounds. [Pg.531]

Stratifying water systems for selective extraction of thiocyanate complexes of platinum metals have been proposed. The extraction degree of mthenium(III) by ethyl and isopropyl alcohols, acetone, polyethylene glycol in optimum conditions amounts to 95-100%. By the help of electronic methods, IR-spectroscopy, equilibrium shift the extractive mechanism has been proposed and stmctures of extractable compounds, which contain single anddouble-chai-ged acidocomplexes [Rh(SCN)J-, [Ru(SCN)J, [Ru(SCN)J -have been determined. Constants of extraction for associates investigated have been calculated. [Pg.257]

Benzyioxycarbonyi chioride (Cbz-Ci, benzyi cbioroformate) [501-53-1] M 170.6, b 103 /20mm, d 1.195, n 1.5190. Commercial material is better than 95% pure and may contain some toluene, benzyl alcohol, benzyl chloride and HCl. After long storage (e.g. two years at 4 , Greenstein and Winitz [The Chemistry of the Amino Acids Voi 2 p. 890, J Wiley and Sons NY, 1961] recommended that the liquid should be flushed with a stream of dry air, filtered and stored over sodium sulfate to remove CO2 and HCl which are formed by decomposition. It may further be distilled from an oil bath at a temperature below 85 because Thiel and Dent [Annalen 301 257 1898] stated that benzyioxycarbonyi chloride decarboxylates to benzyl chloride slowly at 100 and vigorously at 155 . Redistillation at higher vac below 85 yields material which shows no other peaks than those of benzyioxycarbonyi chloride by NMR spectroscopy. LACHRYMATORY and TOXIC. [Pg.130]

In general, the A -methyl derivative of a given compound absorbs at longer wavelengths than the O-methyl derivative. The intensity of a band which appears in aqueous solutions beyond the maximum absorption in alcohol and which is due to the absorption of the betainic species alone, is a measure of the tautomeric equilibrium. The pA"a value of the 2-methyl-hydroxyisoquinolinium chlorides increase in the order 4-hydroxy (4.93), 8-hydroxy (5.81), 6-hydroxy (6.02), 5-hydroxy (6.90), and 7-hydroxy (7.09 in water at 25 °C, respectively) (57JCS5010). Thus, 2-methyl-4-hydroxyisoqui-nolinium chloride is the strongest acid. The UV spectra of 2-methyl-isoquinolinium-5-olate (34) and 2-methyl-isoquinolinium-8-olate (39) were also presented (61BCJ533) and the formation of a quinoid structure of 2-methyl-isoquinolinium-6-olate (38) can also be detected by means of UV-spectroscopy. [Pg.86]

NMR spectroscopy of. 823-824 nucleophilic acyl substitution reactions of, 806-807 reaction with alcohols, 807 reaction with amines, 807... [Pg.1281]

Infrared radiation, electromagnetic spectrum and, 419, 422 energy of. 422 frequencies of, 422 wavelengths of, 422 Infrared spectroscopy, 422-431 acid anhydrides, 822-823 acid chlorides, 822-823 alcohols. 428, 632-633 aldehydes, 428. 730-731 alkanes, 426-427 alkenes, 427 alkynes, 427 amides. 822-823 amines, 428, 952 ammonium salts, 952-953 aromatic compound, 427-428, 534 bond stretching in, 422... [Pg.1301]

The synthesis and purification of cumyl alcohol (CumOH), p-dicumyl methyl ether (DCE)) and 2-chloro-2,4,4-trimethylpentane (TMPC1), and the sources and purification of methyl chloride (MeCl), methylcyclohexane (MCHx), isobutylene have been described [9, 10]. P-Pinene (P-PIN), (Aldrich), was chromatographed over alumina (activity I, Fisher), and freshly distilled over CaH2 under nitrogen according to 1H-NMR spectroscopy and GC analysis the purity was >99%. 2,6-Di-/er/-butylpyridine (DtBP), (Aldrich), anhydrous A,A-dimethylacetamid (DMA), (Aldrich), ethylaluminum dichloride (EtAlCl2), 1.0 M solution in hexanes (Aldrich), and methanol (Fisher) were used as received. [Pg.2]

Absorption spectroscopy of sulphonyl radicals 1093, 1094 of sulphoxides 895, 897, 902-905 Acetoxysulphones 953 electrochemical reactions of 1036, 1037 / -Acyloxysulphones, desulphonylation of 948 Alcohols... [Pg.1195]

Two-dimensional TLC on silica gel G has been used to identify alcohol ether sulfates in liquid laundry detergents. The spots of the chromatograms were examined by UV, IR, and NMR spectroscopy and the spectra compared with those of standard surfactants [283]. [Pg.283]


See other pages where Spectroscopy alcohols is mentioned: [Pg.255]    [Pg.422]    [Pg.486]    [Pg.221]    [Pg.817]    [Pg.891]    [Pg.921]    [Pg.884]    [Pg.299]    [Pg.1069]    [Pg.146]    [Pg.190]    [Pg.632]    [Pg.633]    [Pg.635]    [Pg.637]    [Pg.1283]    [Pg.1297]    [Pg.1297]    [Pg.1308]    [Pg.1315]    [Pg.275]    [Pg.539]    [Pg.199]    [Pg.546]    [Pg.564]   
See also in sourсe #XX -- [ Pg.527 ]

See also in sourсe #XX -- [ Pg.495 ]




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Absorption spectroscopy alcohols

Alcohol IR spectroscopy

Alcohol NMR spectroscopy

Alcohol spectrometry/spectroscopy

Butyl alcohol Spectroscopy

Infrared spectroscopy alcohols

Mass spectroscopy Alcohols

Nuclear magnetic resonance spectroscopy alcohols

Spectroscopy of Alcohols and Phenols

Spectroscopy of Alcohols, Phenols, and Ethers

Ultraviolet visible spectroscopy alcohols

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