Diazotization‐iodination of aromatic amines in water mediated by crosslinked poly(4‐vinylpyridine) supported sodium nitrite

Abstract

An Efficient and simple method for the diazotization of a wide range of aryl amines has been developed by using a polymer-supported sodium nitrite. The diazotization of aryl amines occurred with crosslinked poly(4-vinylpyridine)-supported sodium nitrite, in the presence of concentrated H 2 SO 4 , at low temperature (0-5 C). The obtained diazonium salt, followed by treatment with KI in water at room temperature or at 60 C to produce a various of aryl iodides. The spent polymeric reagent can be regenerated and reused for several times without losing its activity.

Diazotization–cyanation of aromatic amines with crosslinked poly(4‐vinylpyridine)‐supported cyanide ions

“…It is important to note that this polymeric reagent was stable and could be stored for a long time (months) without losing its activity; it could be readily used for the diazotization–cyanation of anilines. [P 4 ‐VP]I was recently prepared and used for the preparation of other functionalized polymers, including polymer‐supported thiocyanate, polymer‐supported carboxylate, polymer‐supported potassium ferrate, polymer‐supported azide ion,51 and polymer‐supported nitrite ion 46–50. Although [P 4 ‐VP]I is well known, [P 4 ‐VP]CN was used the first procedure for the direct diazotization–cyanation of aryl amines, and on the basis of our knowledge, there has been no report in the literature on the synthesis of aryl nitriles based on polymer‐supported cyanide ion.…”

“…In the conversion of aryl amines to the corresponding aryl nitriles, a 3/2 molar ratio of [P 4 ‐VP]CN to amine was needed, although in the conversion of aryl amines to the corresponding aryl iodide, a 3/1 molar ratio of [P 4 ‐VP]I to amine was needed (Table II). 50…”

“…Although polymer‐supported reagents, especially anion‐exchange resins, have been widely applied in organic synthesis,34–52 to the best of our knowledge, there has been no report on the synthesis of aryl nitriles via a dediazoniation–cyanation reaction based on polymer‐supported cyanide ions. Very recently Harrison and Hodge52 reported the synthesis of alkyl nitriles from alkyl halides with the Amberlyst A 26 CN − form.…”

“…Recently, we prepared crosslinked poly(4‐vinylpyridine)‐supported nitrite ions and examined their application in organic transformation, such as in the synthesis of nitro alkanes from alkyl halides,43 azo chromophores,46, 47 N ‐nitrosation of secondary amines,44, 45 nitration of aromatic compounds,48, 49 diazotization–iodination of aromatic amines (Sandmeyer type reaction),50 and diazotization–azidation of aromatic amines 51. In some of these studies, arenediazonium salts were generated in situ .…”

Solvent‐free diazotization–azidation of aryl amine using a polymer‐supported azide ion

“…Although polymer‐supported reagents especially anion exchange resins have been widely applied in organic synthesis,46–62 a literature search shows that there are a few reports in organic transformation based on polymer supported azide reagent. Brenelli et al reported that Amberlite IRA 900 supported azide resin is a highly effective reagent for the conversion of α‐haloketones into α‐azidoketones 59.…”