Selective synthesis in microdroplets of 2-phenyl-2,3-dihydrophthalazine-1,4-dione from phenyl hydrazine with phthalic anhydride or phthalic acid.

Selective synthesis in microdroplets of 2-phenyl-2,3-dihydrophthalazine-1,4-dione from phenyl hydrazine with phthalic anhydride or phthalic acid. Chemistry. 2018 Nov 11;: Authors: Zare RN, Gao D, Jin F, Yan X Abstract Pyridazine derivatives are privileged structures because of their potential biological and optical properties. Traditional synthesis methods usually require acid or base as a catalyst under reflux conditions with reaction times ranging from hours to a few days or require microwave assistance to induce the reaction. Herein, we present the accelerated synthesis of a pyridazine derivative, 2-phenyl-2,3-dihydrophthalazine-1,4-dione, PDHP, in electrosprayed microdroplets containing 1:1 v/v mixture of phenyl hydrazine and phthalic anhydride or phthalic acid. This reaction occurred on the submillisecond timescale with good yield (over 90% with the choice of solvent) without using an external catalyst at room temperature. In sharp contrast to the bulk reaction of obtaining a mixture of two products, the reaction in confined microdroplets yield only the important six-membered heterocyclic product PDHP. Results indicated that surface reactions in microdroplets with low pH values cause selectivity, acceleration, and high yield. PMID: 30417449 [PubMed - as supplied by publisher]
Source: Chemistry - Category: Chemistry Authors: Tags: Chemistry Source Type: research