Infrared nujol mull

Figure 8.4 Schematic view of the hydrogen bistrifluoroacetate complex and infrared (Nujol mull), Raman and INS spectra (from top to bottom) at 20 K, Nujol band C, carbon H, hydrogen O, oxygen F, fluorine. Reproduced with permission from Chem. Phys. 158, F. Fillaux and I Tomkinson, An inelastic neutron scattering study of the proton dynamics in KH (CF COO)2 and CsH(CFiCOO)2, 113, Copyright (1991) Elsevier.

Mason has determined the infrared spectrum of pyrido[3,2-d]-pyrimidin-4(3ff)-one (149, N in position 5) in chloroform solution and as a KBr disc and has suggested that the low frequency of th e NH band (3389 cm ) and high frequency of the C=0 band (1745 cm i) in the solution spectra are indicative of a quasi o-quinonoid form. The infrared spectra of the four pyridopyrimidin-4(377)-ones (149), the four 2,4(ljff,3//)-diones (150), and a number of substituted derivatives, have been determined, as Nujol mulls, in these laboratories. ... 

The sparingly water-soluble triethylammonium saltofBi2H122-is readily converted to the highly water-soluble sodium salt. A carefully weighed sample of the triethylammonium salt is treated with an exactly equivalent amount of standardized aqueous sodium hydroxide. The mixture is heated to effect solution and then boiled to expel the free triethylamine until the vapors are no longer basic. Evaporation to dryness then leaves a crystalline hydrate of Na2Bi2Hi2. The anhydrous salt is obtained by drying at 100°/1 n for 24 hours and has characteristic infrared absorption frequencies as a Nujol mull (exclusive of any frequencies coincident with Nujol) at 2470 (s), 1010 (w), 1070 (m), 770 (w), 727 (m),710 (m),and 700 (m) cm. 1... 

Methylcarborane is an air-stable, white crystalline solid which is soluble in common organic solvents. The infrared spectrum (Nujol mull) contains major absorption bands at 3.90 (s), 8.83 (w), 9.12 (w), 9.69 (w), 9.83 (w), 10.03 (w), and 13.85 (s) p. The proton nuclear magnetic resonance spectrum of a carbon tetrachloride solution of methylcarborane contains a broad —CH resonance of intensity 1 at 6.52 r and a —CH3 resonance of intensity 3 at 8.02 r. 

Triphenylphosphine selenide crystallizes from absolute ethanol as small white needles which melt at 187 to 188°. The compound is very soluble in dichloromethane moderately soluble in hot methanol, hot ethanol, hot acetonitrile, hot benzene, and hot 1-butanol and insoluble in ether and water. The PSe infrared stretching frequency occurs at 562 cm.-1 (Nujol mull). 

The situation with 7V-acyloxy-/V-alkoxyureas and carbamates is similar although infrared data were mostly determined by liquid film or condensed phase (KBr/nujol mull).52,131 However, the limited data for V-acyloxy-TV-alkoxyureas (Table 2, entries 69-72) give amide carbonyl frequencies ca. 1730 cm-1 that are raised by some 37-40 cm-1 by acyloxylation. Values for carbamates (Table 2, entries 73-77) are higher (mostly 1780 cm-1) but are raised to a lesser extent (10-20 cm-1) relative to their parent carbamates. Clearly, carbonyl vibrational frequencies will be influenced strongly by the adjacent amino or alkoxyl group in both analogues. 

Figure 7. Infrared absorption spectrum of CTC-HC1 as Nujol mull. 

Figure 9.21 Infrared spectrum of aspirin, i.e. 2-acetoxybenzoic acid. (Solid aspirin was prepared within a Nujol mull)...

A Nujol mull is a mixture of a solid sample with Nujol, or mineral oil, for the purpose of more conveniently obtaining an infrared spectrum of the solid sample. 

The infrared absorption spectrum of dorzolamide was obtained in a Nujol mull using a Nicolet 51 Op spectrophotometer, and is shown in Figure 7. Assignments for the characteristic absorption bands in the spectrum are provided in Table 1. 

The pentafluorides MoFs (yellow), ReFs (green), OsFs (blue), and UFS (pale yellow-green) are extremely moisture sensitive and must be handled and stored in a dry box. The samples can be stored in Kel-F bottles. With the exception of UF5 these compounds have sufficient vapor pressure so that they can be sublimed. Uranium pentafluoride, on the other hand, is a nonvolatile solid at room temperature. The melting points for these compounds are MoFs, 65° ReFs, 47° OsFs, 70°. The infrared spectra (Nujol mull) show the following broad bands MoFs, 740, 693, 653, 520 cm"1 ReFs, 720, 691, 660, 530 cm 1 OsFs, 710, 690, 655, 530 cm 1 UFS, 620, 565, 510, 405 cm"1. More detailed spectroscopic and powder diffraction data have been summarized elsewhere.5 7... 

Di-p-chloro-bis(i74-l,5-cyclooctadiene)dirhodium(I) is a yellow-orange, air-stable solid. It can be used directly as obtained for preparative purposes5 or as a precursor for homogeneous catalysts.3,4 It can be recrystallized from dichloro-methane-diethyl ether to give orange prisms. The compound is soluble in dichloro-methane somewhat less soluble in acetone and insoluble in pentane and diethyl ether. Characteristic strong bands occur in the infrared spectrum at 819, 964, and 998 cm 1 (Nujol mull). The cyclooctadiene vinylic protons resonate in the 1H NMR spectrum at t 5.7 and the allylic protons at t 7.4-8.3 (deuteriochloroform solution). Other physical properties are given by Chatt.1... 

The infrared spectra of adrenochrome, adrenochrome methyl ether, and 7-iodoadrenochrome in the solid state (Nujol mulls) have... 

The product [(j75-C5Me5)Mo(CO)n]2 is a mixture of the compounds with n = 2 and 3.13 It is not necessary to separate the mixture, since the oxidation described below proceeds with loss of CO. The mixture is moderately air sensitive, but may be stored in an inert atmosphere. The H NMR spectrum of the mixture (200 MHz, CDC13 solution) shows singlets at 1.92 and 1.89 ppm. The infrared spectrum (Nujol mull) shows v(CO) absorption bands at 1925, 1895, 1870, and 1827 cm 1. 

Carbonylchlorocopper(I) is a colorless crystalline substance that decomposes rapidly in the absence of a carbon monoxide atmosphere to give copper(I) chloride and carbon monoxide. The compound is, however, stable for long periods of time if stored under carbon monoxide. Cu(CO)Cl has a polymeric structure,10 which may be described as layers of fused, six-membered, copper-chloride rings in the chair conformation, with terminally bonded carbonyl ligands. The infrared spectrum of Cu(CO)Cl (Nujol mull at 0°C) displays a characteristic large peak at 2127 cm -1 and a vibrational analysis has been reported.13... 

Differential thermal analysis was performed with the DuPont 900 differential thermal analyzer the heating rate was usually 10°C. per minute. To determine heats of reaction, the calorimeter attachment to the Du Pont instrument was employed. Planimeter determinations of peak areas were converted to heat values by using standard calibration curves. For the infrared spectra either a Beckman IR5A instrument or a Perkin Elmer 521 spectrophotometer with a Barnes Engineering temperature-controlled chamber, maintained dry, was used. Specimens for infrared were examined, respectively, as Nujol mulls on a NaCl prism or as finely divided powders, sandwiched between two AgCl plates. For x-ray diffraction studies, the acid-soap samples were enclosed in a fine capillary. Exposures were 1.5 hours in standard Norelco equipment with Cu Ko radiation. For powder patterns the specimen-to-film distance was 57.3 mm. and, for long-spacing determinations, 156 mm. 

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