IR spectral data

For the four smaller systems, determine how well the predicted frequencies compare to the experimental IR spectral data given below. Identify the symmetry type for the normal mode associated with each assigned peak. 

Table 5 IR Spectral Data of Polymers with Copper Sulphate...

The 13C-NMR spectra of 4-7, 9-11 show a close similarity to the spectral data of analogous carbene complexes. The shift differences between the metal carbonyls of the silylene complexes and the related carbon compounds are only small. These results underline the close analogy between the silicon compounds 4-7, 9-11 and Fischer carbene complexes. This view is also supported by the IR spectral data. On the basis of an analysis of the force constants of the vco stretching vibration,... 

IR-spectral data indicated that the dinitrosyl has a cis conformation (123). 

Synthesis of Dicyanates. All dicyanates were prepared according to previously published procedures (2). For IR spectral data see Kohn and Langer (2), for elemental analyses, see reference 10. A specific procedure for the preparation of Z-Tyr-Tyr-Hex-dicyanate has been published (75). 

Ru (0)2(pytn)] " has also been prepared by a similar route " " The IR spectral data of these complexes are listed in Table 4. 

IR spectral data together with microanalytical data have been central to the suggestion that the chloride salt 87 is indeed the product of reaction between the disulfenyl dichloride 86 and trimethylsilyl azide (Scheme 3) characteristic absorptions in the IR spectrum include 1064 (s), 1271 (br, m), 1460 (m, br) <1994IC4537>. 

Table 6 IR Spectral Data for Thietane and Thiete Derivatives...

IR spectral data of many derivatives of thiazolo[3,2-6]-s-triazoles1438, 265 and thiazolo[2,3-c]-s-triazoles265 have been published. There is little information on type A and type C azapentalenes. 

Most fundamental work on the vibrational spectra of azoles appeared in the period 1960-1980. Examples of more recent work include (i) a complete assignment of the gas-phase IR spectrum of indazole (93JCS(F1)4005) (ii) IR spectral data were used to determine the enthalpies of 0—H. . . N and N—H. . . O bonds in complexes of formic acid and 3,5-dimethylpyrazole (87MI301-01) (iii) the vibrational assignment of the Raman spectrum of polycrystalline pyrazole (92MI301-01) based on 3-21G calculations. 

The molecular symmetry of octahydropyridazino[ 1,2-a ]pyridazine (24) has been analyzed using band numbers, frequency coincidences and Raman depolarization factors in the IR and Raman spectra. A centrosymmetric trans conformation was confirmed for this compound (76SA(A)157). IR spectral data also indicate that the carbonyl absorption for pyridazino[l,2-a]pyridazine-l,4-diones (26) occurs at ca. 1625 cm-1 (72TL1885). 

IR spectral data for several pyrimido[4,5-cf]pyridazines have been reported (68JHC845). A comparison of UV data for several 8-amino substituted 5-chloro-2-phenylpyrimido-[4,5-d]pyridazines and 5-amino substituted 8-chloro-2-phenylpyrimido[4,5-(i]pyridazines has been made. The p.Ka values for these compounds have also been reported (Table 3) (76BSF1549). Hiickel MO calculations have been made (66JSP(19)25). 

IR spectral data for 5-aminopyrimido[4,5-d]pyrimidine-2,4-diones indicate a broad NH absorption at 3360 cm-1 for the amino group and absorptions at ca. 1700 and 1650 cm-1... 

IR spectral data for most known 1,2,4-triazines have been published. The absorption of the 1,2,4-triazines in the IR region are those expected for this system. The IR spectrum of the parent compound (1) shows three absorption bands for the C—H stretching vibrations at 3090, 3060 and 3030 cm-1, five bands for C=N and C=C stretching vibrations at 1560, 1529,1435,1380 and 1295 cm-1, three for the C—H in-plane deformations at 1163,1135 and 1113 cm-1, two for the characteristic ring skeleton vibrations at 1050 and 995 cm-1 and three bands for the C—H out-of-plane deformation vibrations at 851,768 and 713 cm-1 (68CB3952). These values are in good agreement with similar bands for pyridine, pyridazine, pyrimidine and pyrazine. Alkyl and aryl derivatives of 1,2,4-triazine show similar bands in their IR spectra, with additional bands from the substituents. 

When cyanamide was electrochemically oxidized at a platinum anode in 2M potassium hydroxide, and the anolyte was neutralized with hydrochloric acid or carbon dioxide, several products were isolated, and to three of these were assigned 1,2,3,5-tetrazine structures. These were the 4-amino-6-cyanamino- (27), 4-amino-6-cyanoguanidino- (28) and 4-ureido-6-cyanoguanidino-l,2,3,5-tetrazines (29) (76BCJ1339). The structures were consistent with the IR spectral data and elemental analyses, but it would be desirable to have unambiguous evidence on these compounds, particularly as their method of synthesis is not an obvious one for forming the connection of three adjacent nitrogen atoms. 

Table 15 Some IR Spectral Data (cm ) for Silver(I) Complexes of Cyanopyridines...

IR spectral data for [Ag(bipy)2]C104 and [Ag(phen)2]C104 are tabulated in Table 20.92 110 111... 

Table 20 IR Spectral Data for [Ag(bipy)JC104,110 [Ag(phen)2]C104lu and [AgCbipyJjNC ffljO92...

Table 42 IR Spectral Data for some Silver(I) Complexes with IV-oxides...

For benzenethiol, crystallization equilibria (equation 21) exist in non-aqueous solvents, such that pale yellow (Me4N)[Ag6(SPh)8l as well as colourless (AgSPh) and yellow (Me4N)2[Ag5(SPh)7] can be isolated.303 Far IR spectral data are available for the latter compound and also for AgSBu and (Et4N)[Ags(SBu,)7].303... 

Table 55 IR Spectral Data (cm l) for Partially Deuterated Silver Amino Add Complexes407...

Primary and secondary silver(I) complexes have been readily prepared by extraction of silver nitrate into a chloroform solution of dithizone. For the secondary complex an excess of silver nitrate was necessary.445 IR spectral data for both complexes are recorded in Table 59.446 The primary complex Ag(HDz) has been reported in hydrated445 and anhydrous446 orange-red forms. The secondary complex Ag2Dz was an anhydrous brown solid. 

Table 59 Principal IR Bands and Far-IR Spectral Data (cm-1) for Dithizone (H2Dz) and its Primary (AgHDz) and Secondary (Ag2Dz) Complexes446...

For the neutral 1 2 monocarboxylic add complexes, their IR absorption spectra showed a shift of the free C02H group from 1700 cm-1 to 1630 cm-1 on coordination. This was indicative of coordination of die carboxylate group. Far-IR spectral data indicated that pyridyl N atoms were also involved in the bonding to the central Ag ion.512... 

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