Trifluoromethylselenolation and Fluoroalkylselenolation of Alkenes by Electrophilic Addition

Abstract

Fluoroalkylselenylated compounds are still underused due to a lack of efficient synthetic methods. Herein, we describe an efficient synthesis of α‐chloro‐β‐fluoroalkylselenolated molecules through electrophilic addition of in situ preformed fluoroalkylselenyl chlorides onto alkenes. The obtained compounds constitute valuable building blocks for further applications.

Environmentally Compatible Access to α‐Trifluoromethylseleno‐Enones

“…These molecules constitute the first examples of α‐perfluoroalkylselenolated enones. As previously observed, the yield decreases with the length of the perfluoroalkyl chain [69] …”

“…As previously observed, the yield decreases with the length of the perfluoroalkyl chain. [69] In a mechanistic point of view, potassium ethoxide, in situ generated by deprotonation of ethanol by K 2 CO 3 , could reasonably be envisaged as 'nucleophilic catalyst' to initiate the reaction (Scheme 4). Such an activation was previously shown in literature with methoxide.…”

Electrophilic trifluoromethylselenolation of terminal alkynes with Se-(trifluoromethyl) 4-methylbenzenesulfonoselenoate

“…Recently, we have described the electrophilic addition of CF 3 SeCl to alkenes to access α-chloro-β-trifluoromethylselenolated molecules [ 65 ]. These products are particularly interesting because the presence of the chlorine substituent opens the way to post-functionalization and thereby to syntheses of more elaborated compounds.…”

Synthetic Approaches to Trifluoromethylselenolated Compounds

“…Access to α‐chloro‐β‐trifluoromethylselenolated molecules was possible from the corresponding alkenes and CF 3 SeCl (Scheme ) . The formation of an episelenonium as a transient species followed by its opening from the released chloride was proposed as mechanism.…”