Recent Advances of Trifluoromethoxylation Reactions Using TFMS and TFBO

Abstract

Trifluoromethoxy (OCF3) group has received increasing attention due to its strong electron‐withdrawing effect and high lipophilicity. However, methods for the synthesis of trifluoromethyl ethers are limited due to the reversible decomposition of trifluoromethoxide anion and limited trifluoromethoxylation reagents. This account mainly focuses on the recent advances of trifluoromethoxylation reactions with our new trifluoromethoxylation reagents.

Advances in the Development of Trifluoromethoxylation Reagents

“…In addition, aryl sulfonic acids bearing an internal basic group failed to give the desired trifluoromethylated products. Availability and thermal stability of TFMS 57 made them attractive trifluoromethoxylation reagents [63].…”

“…In addition, aryl sulfonic acids bearing an internal basic group failed to give the desired trifluoromethylated products. Availability and thermal stability of TFMS 57 made them attractive trifluoromethoxylation reagents [63]. Initially, TFMS 57 (Scheme 35) were employed as efficient nucleophilic trifluoromethoxylation reagents under activation with fluoride anions for enantioselective silvercatalyzed bromotrifluoromethoxylation of alkenes 58 [129].…”

“…More recent approaches include trifluoromethylation of OH group using electrophilic Umemoto [53] and Togni [54,55] reagents. These and other synthetic methods for the preparation of trifluoromethoxy-containing compounds have been extensively reviewed [56][57][58][59][60][61][62][63][64]. In the present article, we provide a short summary of the traditional methods, followed by a critical discussion of the most recently developed trifluoromethoxylating reagents, focusing on their synthetic generality and limitations.…”

Recent trends in dehydroxylative trifluoro-methylation, -methoxylation, -methylthiolation, and -methylselenylation of alcohols

“…Based on mechanistic studies (isotope labelling and 19 F NMR experiments), the author proposed a plausible mechanistic pathway for the above transformation, as depicted in Scheme 7 . 24 The reaction begins with the release of trifluoromethoxide anion (CF 3 O − ) from reagent 12 under the action of a fluoride salt. Subsequently, CF 3 O − undergoes decomposition to produce carbonic difluoride A which, upon esterification with alcohol 11, generates alkyl fluoroformate intermediate B.…”

Study of a Stable “Trifluoromethoxide Anion Solution” Arising from 2,4‐Dinitro‐Trifluoromethoxybenzene

“…However, TFMT [12] and CF 3 OMe [13] are highly volatile, even gaseous, at room temperature. TFMS , [14] TFBO [14a,15] and TFNf [16] are synthesized from expensive electrophilic trifluoromethylating reagents. TFBz [17] is synthesized from a toxic phosgene derivative (triphosgene).…”