Iodo-acetanilide

Halothiophenes, which are not activated through the presence of —I—M-substituents, undergo substitution smoothly under more forcing conditions with copper salts in pyridine or quinoline. Hence 3-cyanothiophene and 5-methyl-2-cyanothiophene have been obtained from the corresponding bromo compounds. 2-Bromothiophene reacts readily with aliphatic cuprous mercaptides in quinoline at 200°C to give thioethers in high yields. The use of the copper-catalyzed Williamson synthesis of alkoxythiophenes from iodo- or bromo-thiophenes and alcoholate has been mentioned before. The reaction of 2-bromothiophene with acetanilide in nitrobenzene in... 

TMBA-ICl2 (l. 42 g, 4.1 mmol) and ZnCl2 (0.7 g) are added to the acetanilide (3.7 mmol) in AcOH (20 ml) and the mixture is stirred at room temperature until the colour has faded. The mixture is concentrated under reduced pressure, aqueous NaHS03 (5%, 10 ml) is added, and the mixture is neutralized with aqueous NaHCOj (5%) and extracted with CH2C12 (4 x 40 ml). The dried (MgS04) extracts are evaporated to yield the iodo-acetanilide. 

The product mixture obtained on photolysis of diaryliodonium salts is, in fact, much more complex than these data suggest. DeVoe et al [22] have identified, in addition to iodobenzene, acetanilide, biphenyl, two iodo-biphenyl isomers in the product mixture from photolysis of Ph2I+PFg in AN or HzO at 254 nm. With the chloride counterion, this list expanded to include chlorobenzene and hydroxybiphenyl (presumably the 2-isomer) Ph2I+I, on the other hand, photolyzed cleanly at 313 nm to iodobenzene. A similar mix of products, including benzene and a third iodobiphenyl isomer was observed by Dektar and Hacker [70] on photolysis of the triflate salt under a variety of conditions (see Table 4, below). 

Iodoaniline 5 03,504 A solution of IC1 (1 mole) is prepared from iodine (127 g) in glacial acetic acid (150 ml) (cf. page 182). When this is dropped, with stirring, into a solution of acetanilide (1 mole) in glacial acetic acid (150 ml) (exothermic reaction ) and the whole is stirred for a further few hours, p-iodoacetanilide is precipitated. After 12 h, the mixture is poured into water (21), and the product is collected and washed with water and dilute sodium hydroxide solution. Recrystallization of this crude material from ethanol gives a 90 % yield of the amide, m.p. 184°, which is hydrolysed by concentrated hydrochloric acid to p-iodo-aniline. 

Diarylamines-i N. A soln. of aniline- N in CCI4 refluxed 0.5 hr. with acetic anhydride and HCl acetanilide- N (Y 99%) refluxed ca. 20 hrs. with iodo-benzene, cuprous iodide, and anhydrous K-carbonate in nitrobenzene N-acetyl-diphenylamine-i N (Y 90%) refluxed 3 hrs. with HCl and alcohol -> diphenyl-amine- N (Y 92%). S. Bulusu and J. R. Autera, J. Labelled Compds. 10, 511 (1974). 

Miura et al. reported the first palladium-free Sonogashira coupling reaction of aryl iodides or vinyl iodides with terminal allqmes in the presence of a copper iodide/triphenylphosphine/potassium carbonate catalyst system (Scheme 15.14). o-Iodo-acetanilide derivatives react with l-allg nes smoothly even at room temperature in the presence of a copper iodide/AT-methylpyrrolidine-2-carboxamide catalyst system (Scheme Various... 

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