Dicyanobenzenes

The feasibility of synthesizing oxovanadium phthalocyanine (VOPc) from vanadium oxide, dicyanobenzene, and ethylene ycol using the microwave synthesis was investigated by comparing reaction temperatures under the microwave irradiations with the same factors of conventional synthesis. The efficiency of microwave synthesis over the conventional synthesis was illustrated by the yield of crude VOPc. Polymorph of VOPc was obtained ttough the acid-treatment and recrystallization step. The VOPos synthesized in various conditions were characterized hy the means of an X-ray dif actometry (XRD), a scanning electron microscopy (SEM), and a transmission electron Microscopy (TEM). 

The introduction of microwave pr ents an excellent new option for the synthesis of VOPc from vanadium oxide, dicyanobenzene, and ethylene glycol. In the present study, the effectiveness of synthesizing crude VOPc liom vanadium oxide and dicyanobenzene rmder the two synthetic methods was investigate by comparing reaction temperatures. Also, the preparation of fine crystal VOPc was investigated from the crude VOPc synthesized at... 

P 32] Pyrene (20 mM), 1,4-dicyanobenzene (40 mM) and sodium cyanide (1 M) were reacted in propylene carbonate and water. A 100 pi solution of pyrene (20 mM), 1.4-dicyanobenzene (40 mM) in propylene carbonate and a 100 pi solution of sodium cyanide (1 M) in water were fed by programmable dual-syringe pumps via fused-silica capillary tubes into a micro-channel chip [29]. Both solutions were fed with equal flow velocity. A 300 W high-pressure mercury lamp was used as light source. After passing an optical filter made of a CUSO4 solution, the whole chip was irradiated after formation of a stable oil/water interface inside. The oil phase was collected at the exit. 

Figure 4.66 Photoq anation of pyrene (PyH) to the corresponding cyanated product (PyCN) in dicyanobenzene (DCB). Left schematic of the flow inside the micro reactor and a microscope image of the chip micro channels. Right GC and mass spectra of samples from micro flow processing [29].

OS 43] [R 14] [P 32] Experiments rrm without NaCN did not yield the cyanated photoproduct ]29]. Therefore, NaCN and not 1,4-dicyanobenzene has to be considered as the source of the CN anion that is incorporated into the pyrene moiety. 

PET reactions [2] can be considered as versatile methods for generating radical cations from electron-rich olefins and aromatic compounds [3], which then can undergo an intramolecular cationic cyclization. Niwa and coworkers [4] reported on a photochemical reaction of l,l-diphenyl-l, -alkadienes in the presence of phenanthrene (Phen) and 1,4-dicyanobenzene (DCNB) as sensitizer and electron acceptor to construct 5/6/6- and 6/6/6-fused ring systems with high stereoselectivity. 

A novel nitrilase was purified from Aspergillus niger K10 cultivated on 2-cyanopyridine. It was found to be homologous to a putative nitrilase from Aspergillus fumigatus Af293. The nitrilase exhibited maximum activity at 45 °C and pH 8.0 with much less activity observed at slightly acid pH. Its substrate preference was for 4-cyanopyridine, benzonitrile, 1,4-dicyanobenzene, thio-phen-2-acetonitrile, 3-chlorobenzonitrile, 3-cyanopyridine, and 4-chlorobenzonitrile. ( )-2-Phenylpropionitrile was only poorly converted by this enzyme and with minimal enantioselectivity. The enzyme was shown to be multimeric (>650 kDa) and be stabilized in the presence of sorbitol and xylitol [57]. 

The regioselectivity of a Rhodococcus rhodochrous nitrilase has been demonstrated for the conversion of 5-fluoro-l,3-dicyanobenzene to 5-fluoro-3-cyano-benzoic acid [62]. The nitrilase was expressed in an Escherichia coli transformant, and a cell-free extract was employed as catalyst (0.14wt% cell-free extract) in 0.1m sodium phosphate buffer (pH 7.2) at 25 °C containing 0.18 m 5-fluoro-l,3-dicyanobenzene. After 72 h, the conversion was >98% and the reaction was stopped by addition of phosphoric acid (pH 2.4) to yield 5-fluoro-3-cyano-benzoic acid as a crystalline product (97% isolated yield). 

Little attention has been devoted to the effects of time-dependent magnetic fields (created by electromagnetic waves) in the absence of a strong magnetic field. Hore and his coworkers [123-125] recently described this effect as the oscillating magnetic field effect (OMFE) on the fluorescence of an exciplex formed in the photochemical reaction of anthracene with 1,3-dicyanobenzene over the frequency range 1-80 MHz. 

Efficient blue emission and good electron affinity and electron-transporting properties were demonstrated for two fluorene copolymers with dicyanobenzene moiety in the main chain, 271a,b (Scheme 2.41) [363], Due to improved electron transport properties, the device... 

The unsymmetrical thiacrown porphyrazines Mg[pz(A3B)], where A = Bn, B = S3 (92a) and Mg[pz(A3B)], where A = Bn, B = S4 crown (93a) were formed by a cross-condensation of excess 3,6-dibutyl-1,2-dicyanobenzene and the corresponding thiaether crown dithiomaleonitrile derivative (91). The porphyrazines were demetalated with TFA and remetalated with either copper or nickel acetate to form Compounds 92c, 93c and 93d (16-18%). 

Other unsymmetrical aminoporphyrazines have been prepared accordingly. The base-catalyzed cross-condensation of bis(dimethylamino)maleonitrile (99) with 1,2-dicyanobenzene (132) produced a statistical mixture of six possible products that represent hybrids between a heterosubstituted aminoporphyrazine and pc (9). The individual yields of all six products depend on the molar ratio of both starting dinitriles. For instance, a 25 1 ratio of dinitriles 99 and 132 produced mainly pz 133 (35%) along with 100 (Scheme 23). 

Calibration of the ion-trap detector for quantification of tetrafluor-1.4 dicyanobenzene and 2,6 dichloro-4-nitroaniline. Finnigan MAT Application Data Sheet ADS 27. 

An asymmetric isoindoline pigment preparation has been claimed, starting from 1,2-dicyanobenzene which is reacted in alcohol and a base, followed by addition of a cyanomethylene compound and subsequently a barbituric acid derivative, whereby all reactions are accomplished without isolation of the corresponding intermediates [22],... 

Interactions between aliphatic amines (n-donors) and benzonitrile139 or dicyanoben-zenes140,141 (jr-acceptors), in n-hexane, are mainly electron donor-acceptor interactions. It is reasonable to assume that the lone-pair of the donor is perpendicular to the plane of the acceptor as reported in 42 for 1,4-dicyanobenzene. 

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