Dimethylaminobenzonitrile

This synthetic process is applicable to the preparation of other aromatic nitriles from aldehydes. The submitters have used it to prepare 5-bromoindole-3-carbonitrile, 7-azaindole-3-carboni-trile, j)-chlorobenzonitrile, 3,4,5-trimethoxybenzonitrile, and p-N,N-dimethylaminobenzonitrile.9 There are several advantages to its use. They include (a) readily available and inexpensive reagents, (b) a simple, time-saving procedure, and (c) fair to good yields of nitrile obtained by a one-step method. 

Rotkiewicz K, Grellmann KH, Grabowski ZR (1973) Reinterpretation of the anomalous fluorescence of p-N, N-dimethylaminobenzonitrile. Chem Phys Lett 19 315-318... 

Fig. 8.2. Examples of molecular rotors. 1 auramine O. 2 crystal violet. 4 p-N,N-dimethylaminobenzonitrile (DMABN). 5 p-/V,/V-dimethylaminobenzylidenemalononitrile. 6 julolidinebenzylidenemalononitrile.

K. A. Al-Hassan and T. Azumi, The role of free volume in the twisted intramolecular charge transfer (TICT) emission of dimethylaminobenzonitrile and related compounds in rigid polymer matrices. Chem. Phys. Lett. 146, 121 (1988). 

Table 14.3 Vertical excited-state energies (eV) of 4-dimethylaminobenzonitrile and 3,5-dimethyl-4-dimethylaminobenzonitrile relative to So gronnd state...

Our review emphasizes three molecular systems 9,9 -bianthryl (BA) [30, 82, 88, 113-121], 4-(9-anthryl)-N,N-dimethylaminoaniline (ADMA) [122-130], and to a lesser extent the well known p-JV,IV-dimethylaminobenzonitrile (DMABN), a compound in the para-cyano-N,JV-dimethylaminoaniline class [1-5, 75-81, 131]. We only briefly mention the arylaminonaph-thalenesulfonates, which have recently been reviewed by Kosower and Huppert [4]. Brief mention is also made of picosecond experiments on diaminophenylsulphones and a number of other systems (see Section III.F). 

DMABN experiments, 59 electronic states related to, 42 Franck-Condon emission in, 48 probability distribution function in, 47 prototype molecules for, 40, 59 4-(9-anthryl)-W,lV-dimethylami noaniline (ADMA), 40 9,9 -bianthryl (BA), 40 />-/V,/V-dimethylaminobenzonitrile (DMABN), 40... 

Bunker et al. also reported approximately three aminofullerene derivatives (3, 32, 33, Fig. 25) that show intramolecular electron transfer from the amino group to the singlet excited state of the fullerene core [189], Although the intramolecular electron transfer shares some characteristics with the classical twisted intramolecular charge transfer in molecules represented by p-N,N-dimethylaminobenzonitrile the amino-C6o derivatives are in fact better classified as redoxdyads [189],... 

R. Cammi, B. Mennucci, J. Tomasi, Fast evaluation of geometries and properties of excited molecules in solution A Tamm-Dancoff Model with application to 4-dimethylaminobenzonitrile. J. Phys. Chem. A 104, 5631 (2000)... 

During the last 6 years, we have studied solvent stabilization of the excited state electron transfer reaction for dimethylaminobenzonitrile (DMABN) (Grassian et al. 1989, 1990 Shang and Bernstein 1992 Warren et al. 1988). Investigation of the cluster behavior of this reaction has led to an important finding that pertains to both condensed phase behavior and the mechanism for the electron transfer,... 

As one might expect, when a donor and an acceptor group are linked by a CT bond, then charge-transfer stabilisation becomes very important. One of the earliest systems to be investigated was 4-dimethylaminobenzonitrile in which the amino group is tilted slightly out of the plane of the benzene ring. 

Fig. 9 Effect of rotation about the Mc2N-C bond upon the electronic energy levels of 4-N,N-dimethylaminobenzonitrile. (From Cowley et al., 1978)...

The discovery of the dual fluorescence of the simple donor-acceptor substituted benzene derivative 4JV,iV-dimethylaminobenzonitrile (DMABN) by Lippert et al. [1] and the subsequent model compound studies by Grabowski et al. [2-6] including rigidized and pretwisted compounds such as MIN, TMABN and CBQ gave birth to the idea of Twisted Intramolecular Charge Transfer (TICT) states. 

The role of free volume on TICT emission of dimethylaminobenzonitrile and related compounds has been examined in polymeric media . The increase in emission with increase in free volume rules out the possibility of specific solute-solvent interactions being responsible for TICT emission in PVA polymer matrices. Fluorescence quenching of phenanthrene and chrysene by KI in met ha nol-et ha no.l, s olu t ion s shows both electron transfer processes and exciplex formation between aromatic hydrocarbon and perturber are important. ... 

Nicolet and Laurence11 studied four phenyl — NALk2 probes not mentioned previously nor included in Table 1 iV,iV-diethyl-3,4-dinitroaniline (38), 4-iV,iV-diethylaminobenzal-dehyde (39), V,lV-dimethylaminobenzonitrile (40) and methyl 4-iV,iV-dimethylamino-benzoate (41), the former two at several temperatures from 0 to 105 °C, the latter two only at 25 °C. The last three probes as well as 6, 42 and 43 mentioned in Table 1 show that the nitro or nitroso chromophore group is not necessary for obtaining useful solvatochromic probes. 

Fig. 16.4 Correlation between the fluorescence lifetime rp and the longitudinal dielectric relaxation time, TL (Eq. (15.19)) of 6-A -(4-methylphenylamino-2-naphthalene-sulfonW,iV-dimethylaniide) (TNSDMA) and 4-N, A-dimethylaminobenzonitrile (DMAB) in linear alcohol solvents. The fluorescence signal is used to monitor an electron transfer process that precedes it. The line is drawn with a slope of 1. (From E. M. Kosower and D. Huppert, Ann. Rev. Phys. Chem. 37,127 (1986) see there for original publications.)...

Absorption and emission spectra of radical copolymer of methyl methacrylate wi h N,N-dimethylaminobenzoyloxyethylmethacrylate ( < 0.017=, Mn = 3 X 10 )(l) and ethyl N,N-dlmethylaminobenzoate (ll) are compared in Figure 2. Except for a small red shift ( 3 nm) in I, the absorption spectra are almost identical. Although the presence of a ground state dimer or solute-solvent complex is known for N,N-dimethylaminobenzonitrile, the best studied TICT compound, there seems to be no such complications for the present studies. This is a favorable condition to study the TICT chromophore in polymers since polymers tend to enhance complicated molecular association even in extremely dilute solution [12] which overshadows the aimed photophysical phenomenon. 

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