key: cord-0738861-3t49bmjo
authors: Radulov, Peter S.; Yaremenko, Ivan A.
title: [Image: see text] Application of BF(3)·Et(2)O in the synthesis of cyclic organic peroxides (microreview)
date: 2020-10-17
journal: Chem Heterocycl Compd (N Y)
DOI: 10.1007/s10593-020-02785-3
sha: aebcebcaaf7cdabd9eb94e75c1b29c10b028eb42
doc_id: 738861
cord_uid: 3t49bmjo

[Image: see text] A summary of recent applications of Lewis acid BF(3)·Et(2)O as a catalyst in the synthesis of cyclic organic peroxides is presented.

Medicinal chemists and pharmacologists recognize cyclic peroxides as an uncharted chemical space for drug design. Cyclic peroxides exhibit antiparasitic, 1 anticancer, 2 antifungal, 3 and antiviral 4 activities. Ethanolic extract of Artemisia annua L. possesses antiviral activity against SARS-associated coronavirus. 5 Such properties have prompted the development of convenient and efficient methods for the synthesis of cyclic peroxides related to natural product -artemisinin. Brønsted acids are mainly used in the synthesis of cyclic peroxides. 6 However, these acids can lead not only to the formation of peroxides, but A summary of recent applications of Lewis acid BF 3 ·Et 2 O as a catalyst in the synthesis of cyclic organic peroxides is presented.

Substituted 1,2-dioxolanes were synthesized from 1,2,4trioxolanes and olefins using BF 3 ·Et 2 O as a catalyst in CH 2 Cl 2 at 0°C. In the presence of BF 3 , the 1,2,4-trioxolane (ozonide) cycle decomposed with the formation of BF 3coordinated carbonyl oxide, which attacked the corresponding alkene to yield 1,2-dioxolane. 9

An ozone-free method for the synthesis of 1,2,4-trioxolanes from 1,5-diketones and H 2 O 2 was developed. 10 In this case, BF 3 ·Et 2 O promoted selective assembly of the ozonide cycle rather than its destruction mentioned above. 9 Bridged 1,2,4-trioxanes were synthesized in low yields via intramolecular cyclization of peroxyketals under action of BF 3 ·Et 2 O. 16 Such an approach could disclose access to new bioactive peroxides. BF 3 ·Et 2 O was also used for the synthesis of bridged 1,2,4,5tetraoxanes from β-diketones. 18 Interaction of gem-bishydroperoxides and acetals in the presence of BF 3 ·Et 2 O is a versatile synthetic route toward substituted unsymmetrical 1,2,4,5-tetraoxanes. 17 Synthesis of β-hydroperoxy-and β-alkoxy-β-peroxylactones Furthermore, BF 3 ·Et 2 O-UHP-alcohol system provided β-alkoxy-β-peroxylactones from β-keto esters. 13

Peroxidation of acetal containing Michael acceptor fragment afforded 1,2-dioxane (nitro analog of plakoric acid). Urea-H 2 O 2 complex (UHP) and BF 3 ·Et 2 O in Et 2 O allowed nucleophilic substitution of only one methoxy group. 11

A.; Ilovaisky, A. I.; Terent'ev, A. O.; Alabugin, I. V

Authors are grateful for the support of the Scientific Schools Development Program by the N. D. Zelinsky Institute of Organic Chemistry.References