Dimethylaniline properties

Chemical properties. As already stated, Petrin is an intermediate in the prepn of numerous mixed esters. Marans et al (Ref 2) prepd a series of Petrin-nitrobenzoate esters by reacting Petrin with the appropriate nitrobenzoyl chloride. They also prepd Petrin-formate, acetate, propionate, oxalate, glutarate, succinate, adipate, and phthalate. An especially important Petrin derivative is Petrin-acrylate. It is prepared by reacting Petrin with a mixt of acrylyl chloride and dimethylaniline (Ref 4)... 

As discussed in Sections 2.6 and 4.2, 5-diazo-l,2,3,4-tetracyanocyclopentadiene (2.52) has many properties that are characteristic of an aromatic diazonium ion. It is therefore not surprising that it forms azo compounds with A A-dimethylaniline or 2-naphthol as coupling components (Webster, 1966). 

Phthalic anhydride condenses with the aniline derivative in the presence of zinc or aluminum chlorides to yield the intermediate benzoyl-benzoic acid, which subsequently reacts with l,3-bis-V,V-dimethylaniline in acetic anhydride to yield the phthalide. The above compound gives a violet-gray image when applied to a clay developer. Clearly this synthesis is also very flexible and variations in shades of color formers have been obtained by varying the aniline components and also by using phthalic anhydrides substituted, for example, by nitro groups or chlorine atoms. Such products have excellent properties as color formers and have been used commercially. Furthermore, this synthetic route is of great importance for the preparation of heterocyclic substituted phthalides, as will be seen later. 

Another approach to improve the color formation properties of Malachite Green lactone has been the introduction of nitrogen atoms into the phthalide ring. Thus, condensation of pyridine-2,3-dicarboxylic acid anhydride with dimethylaniline in the presence of zinc chloride has been shown54 to yield a mixture of the 4- and 7-azaphthalides 11 and 12. 

Although diselenonium-, ditelluronium- and mixed sulfonium-selenonium dications can exhibit either oxidative or electrophilic properties in reactions with nucleophiles, substitution at the onium chalcogen atom is more typical.96 Owing to the increased stability of heavier dichalcogenium-dications, they react only with highly activated substrates such as aniline and tV,A-dimethylaniline, while no reaction is observed with phenol and diphenylamine.113 Reactions of ditelluronium dications with activated aromatics are also not known (Scheme 44).114... 

Nitroanilines were extensively investigated by infrared, Raman, UV/VIS and H NMR spectroscopic methods. In some cases the comparison with similar spectroscopic data of the corresponding tV,/V-dimethylanilines provides simple and consistent conclusions involving geometrical properties of molecules caused by intramolecular hydrogen bonding. 

The formation of charge transfer complexes between N,N-dimethylaniline or N,N-diethylaniline and Cspectroscopic studies, also in view of their potential optical and electronic applications. Even if the spectroscopic properties of Cgo, C70 are complicated by the presence of aggregates in room temperature solutions, the emissions from the excited state charge transfer complexes between fullerenes and iVjV-dialkylani lines are strongly solvent-dependent exciplet emissions are observed in hexane, but in toluene they are absent145. 

A second example of the correlation of isotope effects with substituent properties is given by the reaction between -substituted N,N-dimethylanilines and methyl iodide illustrated in Fig. 10.8.2°-ot-D and incoming group nitrogen KIE s are collected in Table 10.7. 

Nanbo, A. and Nanbo, T. (2002) Mechanistic study on N-demethylation catalyzed with P450 by quantitative structure activity relationship using electronic properties of 4-substituted N,N-dimethylaniline. Quant. Struct.-Act. Relat. 21,613-616. 

Fig. 19. Molecular structure of polytriacetylenes (PTA). The conjugation ends are substituted by donor (dimethylaniline) and acceptor (nitrophenyl) groups to modify the nonlinear optical properties. The lateral OTBDMS ((ferf-butyl)dimethylsilyloxyl) groups serve for improved solubility in the solvent (typically chloroform)...

Like methoxybenzene (see Problem 4 in this chapter and Problem 2(h) from Chapter 1), the partial charges of dimethylaniline (dimethylaminobenzene) are dependent upon the electron-donating properties of nitrogen. Thus, the partial charges are distributed as shown below. 

As noted above, MLCT excited states of diimine metal complexes are both better reductants and oxidants than the ground-state species. This property has been exploited by Gray, Barton, and others for the study of proteins, DNA, and other biological molecules. Flash/quench experiments were first developed to provide a high driving force method to measure rates of electron transfer in proteins. In these experiments an excited diimine complex, typically a member of the Ru(bipy)2(diimine) + family of complexes, is oxidatively quenched with Ru(NH3)6 +, Co(NH3)5CP+, or methyl viologen, or reductively quenched with / -methoxy-A,A-dimethylaniline to yield a highly active redox species. 

These reactions divide the three trinitrotoluenes into two distinct classes. Alpha trinitrotoluene constitutes the one class, in which one molecule of trinitrotoluene reacts with but one molecule of aniline or dimethylaniline while in the second class, one molecule of either the beta or gamma trinitrotoluenes reacts with three molecules of the base, forming decomposition products instead of one addition product. The property of forming addition products seems to hinge npon the symmetrical positions of the nitro-groups. 

In this chapter an attempt has been made to provide an outline of how photoexcitation methods are useful for the student of the kinetic properties of electron-transfer reactions. The emphasis has been on the practice itself, the why and the how. The authors of other chapters of this series of volumes will discuss the manifold results of such studies and put them into the context of the current theories. There is no doubt that photoinitiation of electron-transfer reactions is a powerful technique that is in widespread use. One significant reason for its popularity must be that photoinitiation allows access to timescales on which the fastest of reactions occur. For example, Xu et al. reported recently [145] that the photoinduced electron-transfer reaction between rhodamine 6G and dimethylaniline (DMA) occurs in neat DMA with a lifetime of 85 fs. Reaction lifetimes shorter than this will surely be few and far between. 

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