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Ultrasound-Assisted Green Synthesis of Dialkyl Peroxides under Phase-Transfer Catalysis Conditions.

ABSTRACT: The dialkyl peroxides, which contain a thermally unstable oxygen-oxygen bond, are an important source of radical initiators and cross-linking agents. New efficient and green methods for their synthesis are still being sought. Herein, ultrasound-assisted synthesis of dialkyl peroxides from alkyl hydroperoxides and alkyl bromides in the presence of an aqueous solution of an inorganic base was systematically studied under phase-transfer catalysis (PTC) conditions. The process run in a tri-liquid system in which polyethylene glycol as a phase-transfer catalyst formed a third liquid phase between the organic and inorganic phases. The use of ultrasound provided high yields of organic peroxides (70-99%) in significantly shorter reaction times (1.5 h) in comparison to reaction with magnetic stirring (5.0 h). In turn, conducting the reaction in the tri-liquid PTC system allowed easy separation of the catalyst and its multiple use without significant loss of activity.

SUBMITTER: Kopec D

PROVIDER: S-EPMC6982749 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Ultrasound-Assisted Green Synthesis of Dialkyl Peroxides under Phase-Transfer Catalysis Conditions.

Kopeć Daniel D Baj Stefan S Siewniak Agnieszka A

Molecules (Basel, Switzerland) 20191228 1

The dialkyl peroxides, which contain a thermally unstable oxygen-oxygen bond, are an important source of radical initiators and cross-linking agents. New efficient and green methods for their synthesis are still being sought. Herein, ultrasound-assisted synthesis of dialkyl peroxides from alkyl hydroperoxides and alkyl bromides in the presence of an aqueous solution of an inorganic base was systematically studied under phase-transfer catalysis (PTC) conditions. The process run in a tri-liquid sy ...[more]

PMID: 31905595

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