Chiral Selenide-Catalyzed Enantioselective Allylic Reaction and Intermolecular Difunctionalization of Alkenes: Efficient Construction of C-SCF₃ Stereogenic Molecules

Abstract

New approaches for the synthesis of enantiopure trifluoromethylthiolated molecules by chiral selenide-catalyzed allylic trifluoromethylthiolation and intermolecular difunctionalization of unactivated alkenes are disclosed. In these transformations, functional groups were well tolerated, and the desired products were obtained in good yields with excellent chemo-, enantio-, and diastereoselectivities. This reaction is nicely complementary to enantioselective trifluoromethylthiolation, allylic functionalization, and intermolecular alkene difunctionalization.

A selenium-catalysed para-amination of phenols

“…Selenium-containing small molecules, such as ebselen and its analogues, have also exhibited important antioxidant activity as GPx mimics 12 – 15 . Organoselenium-catalysed reactions have been widely employed in a number of different reactions 16 – 18 , and substantial progress has been made by Breder 19 – 21 , Wirth 22 – 24 , Denmark 25 , 26 , Yeung 27 and Zhao 28 – 31 in recent years. Notably, selenium has emerged as appropriate alternatives to precious metals as catalysts for the construction of C–N bonds 32 – 34 .…”

A cost‐effective shortcut to prepare organoselenium catalysts via decarboxylative coupling of phenylacetic acid with elemental selenium

“…Therefore, this decarboxylative coupling method is of less utility for the purposes of synthesizing pure dibenzyl diselenide or dibenzyl selenide. Fortunately, since the literature demonstrates that both diselenides and selenides are efficient catalysts in oxidation reactions, their mixtures may also be effective catalysts in related reactions. For this reason, we investigated the catalytic activities of mixtures 2 in the useful Baeyer–Villiger oxidation reaction of ( E )‐4‐phenylbut‐3‐en‐2‐one ( 9 ) with H 2 O 2 to produce vinyl ester 10 (Scheme ) …”

“…Recently, much attention has been paid to the eco‐friendly aspects of organoselenium chemistry and among reported works, organoselenium catalysis is one of the most important research directions for its clean procedures, transition‐metal‐free reaction conditions and the metabolizable catalytic Se element that affords a potential alternative to transition metal catalysts . Researchers have reported a series of organoselenium‐catalyzed reactions and this field has seen rapid progress in recent years . However, up to the present, the frequently used method for introducing Se into molecules to synthesize Se catalysts is via the Grignard reagent reaction, which is very tedious to operate and suffers from the use of carcinogenic organohalide starting materials that are hazardous to the environment (Scheme ).…”

Chalkogenbrücken: eine Übersicht

“…In einem aktuellen Beispiel veröffentlichten Zhao et al. eine enantioselektive Difunktionalisierung von Alkenen in Gegenwart chiraler Organoselenidkatalysatoren 13 (siehe Abbildung , rechts, für das entsprechende Intermediat) …”