4-Chlorobenzonitrile

Chlorobenzonitrile [873-32-5] M 137.6, m 45-46°. Crystd to constant melting point from benzene/pet ether (b 40-60°). 

FIGURE 2.30. Redox catalysis induction of Srn1 reactions. Cyclic voltammetry in liquid ammonia + 0.1 M KC1 at —40°C of (a) redox catalyis of the reductive cleavage of 2-chlorobenzonitrile, RX, by 4-cyanopyridine, P. The dotted reversible cyclic voltammogram corresponds to P in the absence of RX. The solid line shows the catalytic increase of the current, (b) Transformation of the voltammogram upon addition of the nucleophile PhS. Adapted from Figure 1 in reference 23, with permisison from the American Chemical Society. 

Fig. 17 Indirect electrochemical induction of Sr I reactions. Cyclic voltammetry of (a) 4-cyanopyridine (2.2 mM) in the absence (—) and presence (—) of 8.9 mM 2-chlorobenzonitrile (b) 4-cyanopyridine (6.6 mM) in the presence of 8.9 mM 2-chloro-benzonitrile and 35 mM PhS -. (Adapted from Amatore el al., 1984b.)...

Chlorobenzonitrile was coupled with p-tolylboronic acid affording the important pharmaceutical intermediate 2-(p-tolyl)benzonitrile in good yield... 

A closely related cyclization (Scheme 82) has been described recently (79JHC753). The imine (134) obtained by the reaction of 2-picolyllithium with 2-chlorobenzonitrile can be cyclized by heating to 200 °C to give 6-aminobenzo[c]quinolizinium chloride (135). Alternatively, the imine can first be hydrolyzed to the ketone (136) which when heated gives 6-hydroxybenzo[c]quinolizinium chloride (137). A benzo derivative, the 8-aminodibenzo-[c,/]quinolizinium ion, was prepared starting with quinaldinyllithium. 

Examples from patents [S. Haber and N. Egger, US Patent 6 140 265 (2000), to Clariant S. Haber and H.-J. Kleiner, US Patent 5 756 804 (1998), to Hoechst-Clariant] describe the synthesis of 2-cyano-4 -methylbiphenyl by reaction of 2-chlorobenzonitrile and p-tolueneboronic acid, in the presence of Na2C03, PdCl2, and triphenylphosphinetrisulfonic acid (4 mol) in a water-toluene system, with a co-solvent miscible with water such as DMSO or... 

Chlorobenzonitrile 3-Chlorobenzonitrile 4-Chlorobenzonitrile 2-Chlorobenzophenone 4-Chloro-2-benzothiazolamine... 

The enamine (223) obtained by reacting 2-chlorobenzonitrile with 2-lithiomethylquinoline (222) is converted into the dibenzo[c/]quinolizinium chloride (224) on heating at 235° (79JHC753), Scheme 51. This two-step process, and related photocyclizations of the azastilbenes (225) obtained by condensation of the appropriate a-methylazines with o-chlorobenzaldehyde (66JOC3683 70JHC1421 91CL1355), could have some potential for development as one-pot procedures. 

Strongly electron-deficient aryl halides react with alcohols without any catalyst. Catalyzed reaction is sometimes better than uncatalyzed reaction as shown by the reaction of 4-bromo-2-chlorobenzonitrile (25) with cyclohexanol. The ether 26 was obtained in 80 % yield using Pd(0)-VI-9 as a catalyst. On the other hand, the uncatalyzed reaction gave equal amounts of 26 and 27 [7]. 

Cyano-4 -methylbiphenyl is produced by coupling of 4-tolylboronic acid and 2-chlorobenzonitrile in the presence of a palladium/snlfonated triphenylphosphine (TPPTS) catalyst in yields higher than 90%. The reaction is conducted at 120 °C in a polyhydric alcohol solvent (e.g., ethyleneglycol), which contains small amounts of sulfoxide or sulfone for catalyst stability reasons. At the end of the reaction two phases form. The catalyst and salts remain in the polar phase, and the product forms the organic phase. This biphasic procedure allows an efficient recycling of the homogeneous catalyst. 

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