Aryldiazonium hexafluorophosphates

ScHiEMANN reaction Aryldiazonium hexafluorophosphates. Aryldiazonium tetrahaloborates. Fluoroboric acid. 

A new deamination procedure involves spontaneous and exothermal decomposition of an aryldiazonium hexafluorophosphate in tetramethylurea. This organic but... 

Once the aryl cation is formed it reacts immediately with the best nucleophile in the reaction mixture. Being a very strong electrophile an aryl cation can even react with very weak nucleophiles. When the best nucleophile is H20—a weak one, indeed—a phenol is produced (Figure 5.41, left). Even when the nucleophile is a tetrafluorobo-rate or a hexafluorophosphate (which are extremely weak nucleophiles), SN1 reactions run their course, and an aryl fluoride is obtained. As the so-called Schiemann reaction, this transformation is carried out by heating the dried aryldiazonium tetrafluorobo-rates or hexafluorophosphates (Figure 5.41, right). 

Deamination Aryidiazonium hexafluorophosphates. Aryldiazonium tetrahaloborates. Di-fluoroamine. Dinitrogen tetroxide (White). Hydroxylamine-O-sulfonic aeid. Hypophos-phorous acid. 3-Nitro-N-nitrosocarbazole. Nitrosyl chloride. Tetramethylurea. Debenzylation of benzoylamines Triethyloxonium fluoroborate. 

Photoinitiators used for epoxy curing include aryldiazonium salts (ArN2+X ), diaryliodonium salts (Ar2l+X ), and onium salts of Group Via elements, especially salts of positively charged sulfur (ArsS+X ). The anions must be of low nucleophilicity, such as tetrafluoroborates or hexafluorophosphates, to promote pol5uner chain growth rather than chain termination. Upon UV irradiation. 

Aryldiazonium tetrafluoroborates and hexafluorophosphates are poorly soluble in nonpolar media but the complexes are soluble due to lipophilization of the salt [14]. 4- -Butylbenzenediazonium tetrafluoroborate is soluble in dichloromethane by virtue... 

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