Dicyanovinyl derivative

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). 

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. 

Pyrrole A, 2-(P,P-dicyanovinyl)-3,5-dimethyl-4-ethylpyrrole, (ref. 69), was converted with sulphuryl chloride to the 5-chloromethyl derivative and then reacted in aqueous ethanolic hydrochloric acid with pyrrole B (3-ethoxycarbonyl-4-methylpyrrole), (ref.70), to afford 3, 4-dimethyl-3-ethyl-4 -ethoxycarbonyl-5-(P,p-dicyanovinyl)-dipyrrylmethane which with 3-methoxycarbonylpropionyl chloride gave 3, 4-dimethyl-3-ethyl-4 -ethoxycarbonyl-5-(P,p-dicyanovinyl)-5 -(3-... 

Later on, they investigated the bis(iron) derivative Fe2 and showed that the presence of the ferrocenyl substituent makes possible a quantitative thermal reopening upon partial or complete oxidation of the redox active system without oxidizing the photochromic core [85, 86]. This process is catalytic in electrons in the case of the perhydro-DTE compound. The thermal reopening of neutral DTE unit is facilitated by electron-withdrawing substituent as gew-dicyanovinyl (Fig. 12). 

The polymer investigated here is a polymethylmethacrylate (PMMA) copolymerised with methacrylate esters of a dicyanovinyl-terminated bisazo dye derivative. A nitro-terminated version of the bisazo dye derivative and a typical monoazo dye. Disperse Red 1 (DRl), derivative is also discussed in [47]. These azo dyes are hereafter referred as 3RDCVXY, 3RNO2, and 2RNO2, respectively. The molecular structure of 3RDCVXY is shown in Figure 3.12a. 

The other monomer needed for the traditional production of PBO is terephthalic acid (TA) or a similar TA derivative. The TA must have extremely high purity and small particle size (50-100 pm) and is easier to handle than the acid chloride [49,50) suitable TA is commercially available. However, the particle size must be reduced to less than 10 pm in order to ensure complete dissolution in poly phosphoric acid (PPA) for the polymerization. Recently, TA has been used as a starting material for the synthesis of 1,4-bis (l-chloro-2,2-dicyanovinyl)benzene (CCB) (Scheme 9.7). Using CCB for PBO polymerization yields a more soluble precursor. 

More-extended Jt-electron systems than pNA have been also widely investigated. In styrene derivatives, those with an amino or methoxy group attached to the benzene ring and two cyano or cyano and alkoxycarbonyl groups attached to the vinyl part have been synthesized, and 2-(2,2-dicyanovinyl)anisol (DIVA) without strong absorption in the visible region was studied as a purple laser generation material. ... 

One of the first derivatives reported was an n-octyl substituted septithio-phene end-capped with dicyanovinyl functional groups (42). The synthesis of compound 42 is shown in Figure 5.26. The septithiophene core (7T) is grown from the inside out via a series of nickel-catalyzed Kumada... 

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