7,7,8,8-tetracyanoquinodimethane complex

Morita Y, Miyazaki E, Umemoto Y, Fukui K, Nakasuji K (2006) Two-dimensional networks of ethylenedithiotetrathiafulvalene derivatives with the hydrogen-bonded functionality of uracil, and channel structure of its tetracyanoquinodimethane complex. J Org Chem 71 5631-5637... 

Only a few X-ray crystal structure determinations on 1,3-dithioles have been carried out. Some typical bond lengths and bond angles of the tetrathiafulvalene (5), l,3-dithiole-2-thione derivative (6) and 1,3-dithiolanes (7) and (8) are given in Tables 2 and 3, respectively. Also bond lengths and bond angles of the radical cation of tetrathiafulvalene in the tetrathiafulvalene-7,7,8,8-tetracyanoquinodimethane complex have been determined <74AX(B)763>. 

Other miscellaneous applications of malononitdle are the synthesis of 7,7,8,8-tetracyanoquinodimethane (46) which is a powerful electron acceptor in the formation of charge-transfer complexes which are of interest because of their conductivity of electricity (96), as well as of 2-chloroben2yhdene malononitnle [2698-41-1] (45) also known as CS-gas, which is a safe lachrymatory chemical used for self-defense devices (97). 

Other oxidants such as TCNQ (7,7, 8,8 -tetracyanoquinodimethane) can be used to oxidize a pentafluorophenylgold(I) complex, as takes place in the case of Q2[Au2(p,-dmit)(C6F5)2], which in the presence of TCNQ evolves in the oxidation of one gold atom giving a gold(III) [108] complex according to Equation 3.20... 

El-Brashy [51] reported the determination of primaquine and other antimalarials via charge-transfer complexes. Powdered sample of primaquine phosphate was dissolved in water and the solution was adjusted to an alkaline pH with 6 M ammonia and extracted with chloroform. The extract was dried with anhydrous sodium sulfate, filtered, and evaporated to dryness under nitrogen and the residue was dissolved in acetonitrile. Portions of the solution were mixed with 0.2% 7,7,8,8-tetracyanoquinodimethane, diluted with acetonitrile, and set aside for 10 min before the absorbance was measured at 845 nm versus a reagent blank. The calibration graphs were linear from 0.4 to 3 pg/mL and recovery was 98%. 

A variety of other highly-strained electron-rich donors also form colored complexes (similar to homobenzvalene) with various electron acceptors, which readily undergo thermal cycloadditions (with concomitant bleaching of the color).209 For example, Tsuji et al.210 reported that dispiro[2.2.2.2]deca-4,9-diene (DDD), with an unusually low ionization potential of 7.5 eV,211 readily forms a colored charge-transfer complex with tetracyanoquinodimethane (TCNQ). The [DDD, TCNQ] charge-transfer complex undergoes a thermal cycloaddition to [3,3]paracyclophane in excellent yield, i.e.,... 

The 2 2 complex formed between /i-CD and reduced tetracyanoquinodimethane shows separate signals for the free and bound CD.203 2D exchange spectroscopy gave an exchange rate of 0.9 s 1 at 30 °C for the exchange between the free guest and the 2 2 complex. The exchange may occur via numerous steps, but no resolution of the intermediate steps could be achieved from the data treatment. 

Another synthesis of olefins has been described in which the desulphurization of thiirans by triphenylphosphine is featured.72 There have been many reports of the synthesis of compounds of the type (63). These form charge-transfer complexes with acceptors such as tetracyanoquinodimethane which have metallic properties. The... 

Fe(abptrz)2(tcnq)2] is an iron(II) complex of the triazole 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole (abptrz) and the 7,7, 8,8 -tetracyanoquinodimethane (tcnq) radical anion whose structure, (132), Mossbauer and IR spectra, and magnetic behavior (thermally induced (280 K) spin crossover -S = 2 -S = 0) have been established. " ... 

Murata T, Saito G, Nishimura K, Enomoto Y, Honda G, Shimizu Y, Matsui S, Sakata M, Drozdova 00, Yakushi K (2008) Complex formation between a nucleobase and tetracyanoquinodimethane derivatives crystal structures and transport properties of charge transfer solids of cytosine. Bull Chem Soc Jpn 81 331-344... 

In the case of the trinuclear [ t-N1,C2-bzimAu]3 (bzim = benzylimidazolate), in addition to the extended structures that form with other metals (see Section 6.3), it also forms supramolecular networks, acting as an electron donor with small organic acids [48]. For example, it reacts with TCNQ (tetracyanoquinodimethane) giving rise to a columnar structure in which each TCNQ molecule is sandwiched between two units of the trinuclear complex in a face-to-face manner. Thus, the repetition of this pattern leads to a stacking of the type (Au3)(Au3)( t-TCNQ)(Au3)... 

Charge transfer complexes have also been investigated as the most attractive candidate materials for high-density electrical data storage.76,77 For instance, sil-ver-tetracyanoquinodimethane (Ag-TCNQ) and copper-tetracyanoquinodimethane (Cu-TCNQ) have been studied for data recording since they exhibit electrical bistability. 

The Menschutkin reaction has been used to prepare poly(viologens) (115) directly (Scheme 31). These polymers were found to be quite useful as polyelectrolyte redox-polymers and for the preparation of conductive polymers when complexed with the 7,7, 8,8 -tetracyanoquinodimethane (TCNQ) radical anion (71MI11100). 

All of the complexes are square planar unless otherwise stated the structures have been determined by X-ray analysis. Bond distances are in pm and nctl in BM. TCNQ is tetracyanoquinodimethane. 

The electrical resistance of complex salts of the 2,4,6-triphenylthia-zinium cation and tetracyanoquinodimethane (TCNQ) has been measured. For one thiazinium cation and 2 mol of TCNQ, the specific resistances were found to be in the range of 5-15 fl/cm (82MI2). 

True CT complexes are formed between unsaturated electron acceptors, among which the derivatives with cyano and nitro groups predominate. The most common strong electron acceptors are 1,2,4,5-tetracyanobenzene, 7,7,8,8-tetracyanoquinodimethane (1), tetracyano-p-benzoquinone (2), tetracyanoethylene (TCNE) (3) and many electron-donor... 

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