Bonding amines

In 1982, Breslow and coworkers reported the first example of iron-catalyzed nitrene C-H bond insertion [29]. They used [Fe(TTP)] as catalyst and PhINTs as nitrene precursor to achieve C-H bond amination of cyclohexane. However, the product yield was low (around 10%). Subsequently, the same authors found that iminoio-dane 7 derived from 2,5-diisopropylbenzenesuIfonamide underwent intramolecular C-H amination efficiently with [Fe(TPP)Cl] as catalyst at room temperature, giving the insertion product in 77% yield (Scheme 29) [85]. 

Iron phthalocyanine is an efficient catalyst for intermolecular amination of saturated C-H bonds. With 1 mol% iron phthalocyanine and 1.5 equiv. PhlNTs, amination of benzylic, tertiary, and ally lie C-H bond have been achieved in good yields (Scheme 31). With cyclohexene as substrate, the allylic C-H bond amination product was obtained in 75% yield, and the aziridination product was found in minor amount (17% yield) [79]. 

That is why logically to assume the possibility of specific interactions also during the swelling process, since the values of parameters of the coal solubility S2, which are determining accordingly to the Flory Renner s equation are differed. It depends on fact if the data for all solvents are taking into account in calculations or such calculations are performed with the exclusion of results for solvents able to be as acceptors of hydrogen bonds (amines, ketones). Different results have been obtained also under application of other methods for calculations, especially of the Van-Krevelen s method [14],... 

New monosubstituted cobaltocenium derivatives functionalized with hydrogen-bonding amine groups (Fig. 39) have been prepared and the... 

Solubility in water Because of hydrogen bonding, amines with low molecular masses (four or less carbon atoms) are completely miscible with water. The solubility of an amine decreases as the number of carbon atoms increases. 

X and Y may be H2O or halide groups. A number of reactions of Pd(II) appear to fit this scheme.Ring opening and the subsequent slower displacement of single bonded amine are kinetically separable with M = Au(III), and each step proeeeds via a normal nucleophilic attack. 

The fact that complex 38 does not react further - that is, it does not oxidatively add the N—H bond - is due to the comparatively low electron density present on the Ir center. However, in the presence of more electron-rich phosphines an adduct similar to 38 may be observed in situ by NMR (see Section 6.5.3 see also below), but then readily activates N—H or C—H bonds. Amine coordination to an electron-rich Ir(I) center further augments its electron density and thus its propensity to oxidative addition reactions. Not only accessible N—H bonds are therefore readily activated but also C—H bonds [32] (cf. cyclo-metallations in Equation 6.14 and Scheme 6.10 below). This latter activation is a possible side reaction and mode of catalyst deactivation in OHA reactions that follow the CMM mechanism. Phosphine-free cationic Ir(I)-amine complexes were also shown to be quite reactive towards C—H bonds [30aj. The stable Ir-ammonia complex 39, which was isolated and structurally characterized by Hartwig and coworkers (Figure 6.7) [33], is accessible either by thermally induced reductive elimination of the corresponding Ir(III)-amido-hydrido precursor or by an acid-base reaction between the 14-electron Ir(I) intermediate 53 and ammonia (see Scheme 6.9). 

A C—C bond is weaker and breaks more easily and more often than a C—H bond. Amines A and B both lose a CH, (m = 15) 59- 15 = 44. 

Bonded amine Si-O-Si-C -ch2ch2ch2-nh2 Polar bonded phase Selectivity is modified with respect to silica through the aminopropyl functionality the propyl linkage can interact... 

Marko Varga et al. [45] found that a cleanup column prior to the separation column, packed with a chemically bonded amine material (Nucleosil 5 HN2) was found to be effective in removing interfering humic substances. No influence was found from humic substances in concentrations up to 45 pg L 1 on ion chromatographic analysis of nitrate and sulphate (10-100mg L ) after passage through the cleanup column. 

This technique has been applied by Iskandami and Petrzyk [316] to the determination of nitrate and nitrite in water. Chemically bonded amine materials have been used to remove interference by humic substances prior to the ion chromatographic determination of nitrate and sulphate in non saline waters. 

XPS studies of free and surface-bonded amine groups... 

The removal of H20 from the system shifts the reversible equilibrium to the hydrogen-bonded amine on the left, with a chemical shift of 25 - 27 ppm. The addition of H20 shifts the equilibrium to the hydrated Brdnstedt complex, having a chemical shift of 21 - 22 ppm. From the relative pK, values of the surface silanols (5.0 - 9.5) and the water (14), it is clear that the proton will be abstracted from the surface rather than from the adsorbed water molecule. 

An alternative mechanism for the base-promoted reaction of silanes with silica has been described by Blitz et al.83 In this mechanism, the base attacks directly to the surface silanols. The bonded amine renders the silanol more nucleophilic which then attacks the silicon atom of an approaching silane, giving rise to a pentacoordinate intermediate. 

Specifically, the tetrahedral intermediates B and D are formed in amide reductions with LiAlH4 and DIBAL, respectively. Their decomposition in principle could affect the C—O bond (—> —> —> amine) or the C—N bond (—> —> —> alcohol). There are two factors that provide an advantage for the C—O bond cleavage ... 

Friestad GK (2009) Addition of carbanions to azomethines. In Enders D, Shaumann E (eds) Science of synthesis vol 40a compounds with one saturated carbon-heteroatom bond amines and ammonium salts. Thieme, Stuttgart... 

The most important reaction of amino acids is the formation of peptide bonds. Amines and acids can condense, with the loss of water, to form amides. Industrial processes often make amides simply by mixing the acid and the amine, then heating the mixture... 

IR evidence of N— 01 H bonds amine coximlexes of platinous chloride. 

Like ammonia, amines are polar compounds and, except for tertiary amines, can form intermolecular hydrogen bonds. Amines have higher boiling points... 

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