Dicyanovinyl

Fig. 4 Ground-state and excited-state energies of the TICT complexes thioflavin T (a) and 9-(dicyanovinyl)-julolidine (DCVJ) (b) as a function of the intramolecular rotation angle (data from Stsiapura et al. [13] and Allen et al. [14]). In both cases, energy levels were determined by quantum mechanical simulations. For thioflavin T, the energy difference between Si and S0 corresponds to approximately 400 nm in the planar state and 470 nm in the twisted state. In the case of DCVJ, the energy differences correspond to 310 and 960 nm, respectively. The DCVJ energy levels reflect a rotation around the vinyl double bond...

Fig. 6.7. Viscosity sensitive fluorophores molecular rotors. DCVJ = 9-(dicyanovinyl)-julolidine, CCVJ = 9-(carboxy-2-cyano)vinyl julolidine, CMAM = 2-cyano-3-(p-dimethyl-aminophenyl)acrylic acid, methyl ester.

King, R.B. and Diefenbach, S.P., Transition-metal cyanocarbon derivatives. 5. Reactions of (l-chloro-2,2-dicyanovinyl)manganese derivatives with trialkyl phosphites. A novel variant of the Michaelis-Arbuzov reaction leading to [2,2-dicyanovinylphosphonato]metal complexes, Inorg. Chem., 18, 63, 1979. 

Electron acceptor dicyanovinyl and oxadiazole substituents have been recently introduced into phenylene units of the PPV block copolymers (179,180) [211]. Blue and blue-greenish PL emission was observed for 179 and 180, respectively, but the PLQY was relatively low even in solution (13 and 24%) and no EL device has yet been reported. 

Uncharged styryl (methine) disperse dyes were originally introduced to provide greenish yellow colours on cellulose acetate fibres. One such dye still in use is Cl Disperse Yellow 31 (6.226), which is made by condensing 4-(N-butyl-N-chloroethylamino)benzaldehyde with ethyl cyanoacetate. Suitable compounds for polyester usually contain the electron-accepting dicyanovinyl group, introduced with the aid of malononitrile. An increased molecular size leads to improved fastness to sublimation, as in the case of Cl Disperse Yellow 99 (6.227). A novel polymethine-type structure of great interest is present in Cl Disperse Blue 354 (6.228), which is claimed to be the most brilliant blue disperse dye currently available [85]. 

Figure 1.11 Solvatochromic dyes Nile Red (a) and an a-pcrlluoroalky-/),/)-dicyanovinyl compound (b)...

The reactions of methyl 2-formyl-677 or 6-substituted furo[2,3-. ]pyrrole-5-carboxylates 31d-f or 154 <1997MOL69, 1999CCC1135> with malononitrile, methyl cyanoacetate, and 2-furylacetonitrile, respectively, afforded the corresponding methyl 2-(2,2-dicyanovinyl)-677- or 6-substituted furo[2,3-. ]pyrrole-5-carboxylates 294a-d, methyl 2-[2-cyano-2-(methoxycarbonyl)vinyl]-677- or 6-substituted furo[2,3-. ]pyrrole 5-carboxylates 295a-d, and methyl... 

Dispersion polymerizations of methyl methacrylate ntUizing poly(l,l,-dihydroper-fluorooctyl acrylate) as a steric stabilizer in snpercritical CO2 were carried out in the presence of helium. Particle size and particle size distribution were found to be dependent on the amonnt of inert helium present. Particle sizes ranging from 1.64 to 2.66 pm were obtained with varions amounts of helium. Solvatochromic investigations using 9-(a-perflnoroheptyl-p,p-dicyanovinyl)julolidine indicated that the solvent strength of CO2 decreases with increasing helium concentration. This effect was confirmed by calcnlations of Hildebrand solubility parameters (Hsiao and DeSimone, 1997). 

A triplet dianion of l,3,5-tris(dicyanovinyl)-substituted benzene can be produced by potassium reduction.38 Simulation of the EPR spectrum gave D = 0.0102 cm-1 from which a point dipole distance of 6.4 A was calculated. 

In contrast to the reactivity of the nitroethylenes, acrylonitrile generally reacts with indoles to form the l-(2-cyanoethyl) derivatives (B-70MI30500,79MI30501), whereas Michael addition at the 3-position requires the catalytic effect of copper(II) salts. The addition-elimination reaction of pyrroles and indoles with l,l-dicyano-2-ethoxyethylene proceeds in low yield (<30%) to give the dicyanovinyl derivatives, which can be converted by standard procedures into the formyl compounds (81H(16)1499). Tetracyanoethylene forms charge transfer complexes with indoles, which collapse to the Michael adduct anions and subsequently eliminate a cyanide ion with the formation of the tricyanovinylindole (B-70MI30500). 

An analogous investigation was made [27] with donor-acceptor pairs such as those depicted in Fig. 7. The donor-acceptor pairs I-V presented in this figure are separated by various numbers, n, of similar chemical bonds, a so-called "n-bond system. The more electron-attracting group is the dicyanovinyl group. In ref. 27, the n-bond systems were investigated for n = 4, 6, 8, 10, 12. Pulse radiolysis experiments under conditions similar to... 

Structure 3 Benzophenoxazine ETH 5350 (Fluka) Dicyanovinyl alkylated 640 PVC/DOS Flow cell/A nh3 1991 [42]... 

Figure 18. On irradiation, a new peak appears, indicating the formation of a new species with a less negative reduction potential. After irradiation for 16 min, 23a showed a distinctly different I/E trace, as shown in Figure 19. This observation indicates that the VHF form 23b is reduced at a less negative potential, due to its jt-acceptor dicyanovinyl substituent.

Thermolysis of 3-(2,2-dicyanovinyl)-4-(l-piperidyl)pyridine (15, X = CH2) in DMSO produces the naphthyridine (16, X = CH2) by means of the "tert-amino effect" proposed by Meth-Cohn and Suschitzky <95SL622>. Where, however, X is a N, O or S an alternative cyclisation takes place, when the pyridoazepines (17) are formed. This new variant of the "rert-amino effect" is postulated to arise by the intermediate formation of (18). 

Monocyclic azetidin-2-ones have been explored for their anticancer activity. The (3A, /y)-l-(4-methoxyphenyl)-3-methyl-4-(2-acetoxybenzoyloxymethyl)-4-(2,2-dicyanovinyl)azetidin-2-ones have shown anticancer activity in vitro with respect to a wide range of monolayer cultures of cancer cells <2003GHE587>. 7ra r-l-V-chrysenyl-3-acetoxy-4-phenylazetidin-2-one 565 and l-V-phenanthrenyl-3-acetoxy-4-phenylazetidin-2-one 566 have shown selective anticancer activity against two leukemia and carcinoma cell lines <2004BMC2523>. 

The electron transporting 9-(dicyanovinyl)thioxanthene moiety and electrooptically active vinylaniline units have been combined in the succinate esters 601. The compounds exhibit good photorefractive properties with high optical quality <2003SM(139)11>. 

---