k 2022

PERHALOACETALDEHYDES IN THE ENANTIOSELECTIVE ORGANOCATALYZED FRIDEL-CRAFTS ALKYLATION: REACTION CONDITIONS DEVELOPMENT

ŠVESTKA, David, Jan OTEVŘEL and Pavel BOBÁĽ

Basic information

Original name

PERHALOACETALDEHYDES IN THE ENANTIOSELECTIVE ORGANOCATALYZED FRIDEL-CRAFTS ALKYLATION: REACTION CONDITIONS DEVELOPMENT

Authors

ŠVESTKA, David (203 Czech Republic, belonging to the institution), Jan OTEVŘEL (203 Czech Republic, belonging to the institution) and Pavel BOBÁĽ (703 Slovakia, belonging to the institution)

Edition

50th Conference SYNTHESIS AND ANALYSIS OF DRUGS, 2022

Other information

Language

English

Type of outcome

Prezentace na konferencích

Field of Study

30104 Pharmacology and pharmacy

Country of publisher

Czech Republic

Confidentiality degree

není předmětem státního či obchodního tajemství

RIV identification code

RIV/00216224:14160/22:00126749

Organization unit

Faculty of Pharmacy

ISBN

978-80-280-0110-0

Keywords in English

Friedel-Crafts; Cinchona; phenol; trihaloacetaldehyde

Tags

rivok, ÚChL
Změněno: 26/9/2022 08:16, Mgr. David Švestka

Abstract

V originále

Trihaloacetaldehydes represent useful electrophiles in asymmetric processes that can grant access to many biologically active compounds containing CX3 groups. One of the possibilities for obtaining aromatic trihaloethanols is the asymmetric organocatalyzed Friedel-Crafts reaction between phenol and trihaloacetaldehyde, which represents the subject of our current research. As such, we started with the extensive three-phase catalyst screening. Cinchona alkaloid-based amide derivatives showed the best enantioselectivity in the initial stage of catalyst testing. Improvement of the catalyst structure revealed 3,5-dinitrobenzamide of 9- aminoepicinchonidine as the lead catalytic molecule. Next, a series of optimizations were performed to establish the most suitable reaction conditions. Having the optimal parameters in hand, the reaction between electron-rich phenols and trihaloacetaldehydes or their hemiacetals conveniently provided enantioenriched adducts with good to excellent enantiomeric ratios (up to 99:1) within 12–24 h at 25 °C. The substrate scope included 29 derivatives containing –CF3, –CCl3, –CF2Cl, and –CF2Br groups. Additionally, several stereoretentive downstream transformations of products were identified. This work constitutes the first organocatalyzed method for the synthesis of chiral non-racemic 2,2,2-trihalo-1- hydroxyalkylphenols.

Links

MUNI/A/1510/2020, interní kód MU
Name: Vývoj asymetrické organokatalytické syntézy trihalogenmethylkarbinolů
Investor: Masaryk University
MUNI/A/1682/2020, interní kód MU
Name: Návrh, syntéza a hodnocení derivátů skupin léčiv s inhibiční enzymatickou aktivitou
Investor: Masaryk University
Displayed: 13/11/2024 18:08