4-Aminobenzophenone

Effect of solvents on the bulk growth of 4-aminobenzophenone single crystals: a potential material for blue and green lasers.[Pubmed:25795606]

Spectrochim Acta A Mol Biomol Spectrosc. 2015 Jun 15;145:329-332.

Although 4-Aminobenzophenone (4-ABP) is the best derivative of benzophenone with 260 times higher second harmonic generation (SHG) efficiency than potassium dihydrogen phosphate (KDP), growth of high quality bulk crystal still remains a difficult task. In the present work, the effect of solvents on solubility and growth aspects of 4-ABP was investigated to grow inclusion free 4-ABP crystals. The growth processes were discussed based on solute-solvent interaction in two different growth media of ethyl acetate and ethanol. The growth rate and thereby solvent inclusions are relatively higher in ethyl acetate grown crystal than the crystal grown from ethanol. The structural, thermal and optical properties of 4-ABP crystals were studied. The enthalpy of 4-ABP melting process was estimated from differential thermal analysis. The optical transmission study shows that 4-ABP crystals grown from ethanol has high transparency compared to ethyl acetate grown sample due to solvent inclusion in the later crystal.

Synthesis, crystal growth, characterization and theoretical studies of 4-aminobenzophenonium picrate.[Pubmed:25062048]

Spectrochim Acta A Mol Biomol Spectrosc. 2015 Jan 25;135:46-54.

Single crystals of 4-aminobenzophenonium picrate (4ABPP) were grown by slow evaporation of a mixed solvent system methanol-acetone (1:1,v/v) containing equimolar quantities of picric acid and 4-Aminobenzophenone. The proton and carbon signals are confirmed by nuclear magnetic resonance spectroscopy. The various functional groups present in the molecule are identified by FT-IR analysis. Optimized geometry, first-order molecular hyperpolarizability (beta), polarizability (alpha), bond length, bond angles and excited state energy from theoretical UV were derived by Hartree-Fock calculations. The complete assignment of the vibrational modes for 4-aminobenzophenonium picrate was performed by the scaled quantum mechanics force field (SQMFF) methodology using potential energy distribution. Natural bond orbital (NBO) calculations were employed to study the stabilities arising from charge delocalization and intermolecular interactions of 4ABPP. The atomic charge distributions of the various atoms present in 4ABPP are obtained by Mulliken charge population analysis. The as-grown crystal is further characterized by thermal and optical absorbance studies.

Nickel-NHC-catalyzed alpha-arylation of acyclic ketones and amination of haloarenes and unexpected preferential N-arylation of 4-aminopropiophenone.[Pubmed:17559270]

J Org Chem. 2007 Jul 6;72(14):5069-76.

Arylation of both acyclic ketones and primary and secondary amines was achieved using a new, simple, stable, and easy-to-access nickel(II)-halide complex bearing mixed PPh3/N-heterocyclic carbene ligands as a catalyst precursor. Acyclic ketones were first arylated at the alpha-position with the nickel catalyst. On the other hand, less basic amines, such as diphenylamine and 4-Aminobenzophenone, were more favorable in the catalytic amination of haloarenes than basic amines, contrary to previous reports. N-Arylation of 4-aminopropiophenone was found to proceed selectively without causing alpha-arylation of the ketone group.

Stimuli-responsive properties of N-isopropylacrylamide-based ultrathin hydrogel films prepared by photo-cross-linking.[Pubmed:16768529]

Langmuir. 2006 Jun 20;22(13):5911-5.

To develop stimuli-responsive ultrathin polymer films on a solid substrate, a novel photo-cross-linkable polymer with both temperature- and pH-responsive properties was prepared. The photoreactive 4-Aminobenzophenone (BP) was introduced onto the side groups of poly(N-isopropylaclylamide-co-2-carboxyisopropylaclylamide) [poly(NIPAAm-co-CIPAAm)]. This copolymer was designed for highly random sequences of comonomers. After the formation of spin-coated polymer films on a solid substrate, UV-light irradiation started the cross-linking reaction. The spin-coating processes and stability of the polymer films were quantitatively monitored by a quartz crystal microbalance (QCM), and the thickness was estimated using an atomic force microscope (AFM). These measurements confirmed the formation of a very plain polymer film, and the film thickness was precisely controlled by the concentration of the polymer solution used for spin coating. Moreover, the obtained films showed a high stability due to the cross-liking reaction and UV irradiation. Cyclic voltammetry using potassium ferricyanide revealed that the ions could permeate the photo-cross-linked ultrathin polymer films. The permeability of the ultrathin hydrogel films was dramatically changed by varying the pH and temperature of the aqueous media. These observations suggest that the preparation of isopropylacrylamide-based stimuli-responsive ultrathin hydrogel films is possible.

Inversion of 4-methoxybenzophenone triplet in aqueous solutions.[Pubmed:12665309]

Photochem Photobiol Sci. 2002 Sep;1(9):704-8.

The triplet state of 4-methoxybenzophenone (4-MBP) has been investigated by laser flash photolysis and emission techniques in several solvents. In non-polar cyclohexane, 4-MBP triplet has an (n,pi*) configuration with the typical triplet-triplet absorption spectrum of benzophenone (lambda(max) ca. 525 nm). However, due to the proximity of the two lowest triplet states of different configuration, some unusual features are observed in polar solvents. Thus, 4-MBP shows in aqueous solutions a transient absorption spectrum with lambda(max) at 450 and 680 nm, which can be attributed to a T1 (pi,pi*) state. Further, transient absorption spectra due to T1 (n,pi*) and T2 (pi,pi*) being simultaneously populated are observed upon laser excitation of 4-MBP in polar solvents such as acetonitrile or methanol. The triplet state inversion (n,pi* to pi,pi*) is also detected by the measurement of triplet quenching rate constants by 1,4-cyclohexadiene (a good hydrogen donor) in acetonitrile and water (kH ca. 2 x 10(8) and 5 x 10(5) M(-1) s(-1), respectively) and by the determination of room-temperature phosphorescence (the emission quantum yield at room-temperature decreases from 0.004 in acetonitrile to less than 1 x 10(-6) in water). Further, the energy of the 4-MBP triplet state is ca. 288 kJ mol(-1) both in polar and non-polar organic solvents, while in water it drops to 275 kJ mol(-1). The photophysical properties of 4-MBP are compared with those of 4-Aminobenzophenone (4-ABP), which also possesses an electron-donating group. In polar organic solvents such as acetonitrile, the transient absorption spectrum and the quenching rate constant of hydrogen abstraction for triplet 4-ABP are practically the same as those obtained for 4-MBP in aqueous solutions. On the other hand, a small T2 (pi,pi*) contribution is observed in the triplet-triplet absorption spectrum of 4-ABP in cyclohexane.

Non-thiol farnesyltransferase inhibitors: evaluation of different AA(X)-peptidomimetic substructures in combination with arylic cysteine replacements.[Pubmed:12112033]

Arch Pharm (Weinheim). 2002 Apr;335(4):135-42.

In the course of our studies on non-thiol farnesyltransferase inhibitors based on the 2, 5-diaminobenzophenone AAX-peptidomimetic substructure, we have developed the (4-nitrophenyl)butyryl (R(1)), the (2-naphthyl)acryloyl (R(2)), the 4-nitrocinnamoyl (R(3)), and the 5-(4-nitrophenyl)furylacryloyl (R(4)) groups as useful cysteine replacements. In this study, we combined these four groups with other AA(X)-peptidomimetic substructures (5-10: R = H) reported in the literature. The 5-(4-nitrophenyl)furylacryloyl moiety (R(4)) turned out to be the most useful non-thiol cysteine replacement yielding in all cases the most active inhibitors. By combination of this 5-(4-nitrophenyl) furylacryloyl moiety (R(4)) with the structurally simple AAX-peptidomimetics 4-Aminobenzophenone (5) and 4-aminodiphenylsulfone (6) potent, readily accessible non-thiol farnesyltransferase inhibitors were obtained (IC(50) = 12 nMand 10 nM).

Selective synthesis of novel cyclic phenylazomethine trimers[Pubmed:10970311]

J Org Chem. 2000 Sep 8;65(18):5680-4.

Novel cyclic phenylazomethine trimers (CPAs) were synthesized in a one-step dehydration of the 4-Aminobenzophenone derivatives in the presence of TiCl(4) or p-toluenesulfonic acid (PTS). The CPAs were isolated in over 90% yield under nondilute conditions. When using TiCl(4) as the dehydration agent, the induction of bulky substituents at the alpha-position of the substrate enhanced the yields of the CPAs. On the other hand, PTS served as an effective catalyst for the synthesis of the phenyl-substituted CPA. This different reactivity between TiCl(4) and PTS depends on the dehydration mechanism being dominated by a kinetic process or thermodynamic one. The obtained CPAs were confirmed by NMR, UV-vis spectra, and MM2 calculation to have only a Z conformation and a nonconjugated structure compared to the linear oligophenylazomethines (OPAs) and the aniline-capped OPAs (OPA's).

Linear electro-optic effect in the organic crystal 4-aminobenzophenone.[Pubmed:18250716]

Appl Opt. 1997 Jan 20;36(3):613-6.

The linear electro-optic effect in single crystals of 4-aminobenzphenone (ABP) is reported together with calibration data on LiNbO(3). For ABP the linear electro-optic coefficients r(22) and r(32) at 488 nm were found to be 2.12 and 5.05 pm/V, respectively, with the corresponding reduced half-wave voltages being 49.4 +/- 0.1 and 9.3 +/- 0.1 kV. For LiNbO(3) the half-wave voltage was found to be 4.0 +/- 0.1 kV at 632.8 nm and 2.4 +/- 0.1 kV at 488 nm.

Further application of the diazotizationcoupling spectrophotometric technique to the determination of aromatic amines with 8-amino-1 -hydroxynaphthalene-3,6-disulphonic acid and N-(1-naphthyl)-ethylenediamine as coupling agents.[Pubmed:18963593]

Talanta. 1984 Apr;31(4):295-7.

Twenty-two aromatic amines are determined by the diazotization-coupling spectrophotometric technique, using 8-amino-1-hydroxynaphthalene-3,6-disulphonic acid (H-acid) and N-(1-naphthyl) ethylenediamine (N-na) as coupling agents. The following are determined by both methods: 2-and 4-ethylaniline, 4-aminobenzonitrile, 3- and 4-aminoacetophenone, 4-Aminobenzophenone, 4-iodoaniline, 2,5-dichloroaniline, 4-aminohippuric acid, 2-aminobenzyl alcohol, 3-aminobenzamide, sulphathiazole, 2-, 3- and 4-methoxyaniline and 2,4-, 3,4- and 3,5-dimethylaniline. It is possible to determine 2,3- and 2,5-dimethylaniline only by the H-acid method, but 2,6-dimethylaniline cannot be determined by either method. 2-Aminobenzamide can only be determined by the N-na method. In the application of the H-acid method to the methoxyanilines and dimethylanilines, the colour is developed by adding a large excess of sodium bicarbonate and H-acid. In the application of the N-na method to the ethylanilines, methoxyanilines and 2,4-, 3,4- and 3,5-dimethylanilines, the colour is developed by addition of a large excess of N-na reagent and allowing the solution to stand overnight.