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Electrochemical Nitration with Nitrite.

ABSTRACT: Aromatic nitration has tremendous importance in organic chemistry as nitroaromatic compounds serve as versatile building blocks. This study represents the electrochemical aromatic nitration with NBu₄ NO₂ , which serves a dual role as supporting electrolyte and as a safe, readily available, and easy-to-handle nitro source. Stoichiometric amounts of 1,1,1-3,3,3-hexafluoroisopropan-2-ol (HFIP) in MeCN significantly increase the yield by solvent control. The reaction mechanism is based on electrochemical oxidation of nitrite to NO₂ , which initiates the nitration reaction in a divided electrolysis cell with inexpensive graphite electrodes. Overall, the reaction is demonstrated for 20 examples with yields of up to 88 %. Scalability is demonstrated by a 13-fold scale-up.

SUBMITTER: Blum SP

PROVIDER: S-EPMC9298355 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Electrochemical Nitration with Nitrite.

Blum Stephan P SP Nickel Christean C Schäffer Lukas L Karakaya Tarik T Waldvogel Siegfried R SR

ChemSusChem 20211022 22

Aromatic nitration has tremendous importance in organic chemistry as nitroaromatic compounds serve as versatile building blocks. This study represents the electrochemical aromatic nitration with NBu<sub>4</sub> NO<sub>2</sub> , which serves a dual role as supporting electrolyte and as a safe, readily available, and easy-to-handle nitro source. Stoichiometric amounts of 1,1,1-3,3,3-hexafluoroisopropan-2-ol (HFIP) in MeCN significantly increase the yield by solvent control. The reaction mechanism ...[more]

PMID: 34583423

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