One-pot preparation of (RSe)2CF2 and (RS)2CF2 compounds via insertion of TMSCF3-derived difluorocarbene into diselenides and disulfides

Difluorocarbene-Mediated Cascade Cyclization: The Multifunctional Role of Ruppert–Prakash Reagent

“…Trifluoromethyl­(trimethyl)­silane, known as the Ruppert–Prakash reagent, has been widely implemented in various trifluoromethylation reactions . Its utility as a difluorocarbene precursor was disclosed by Hu and Prakash, wherein difluoromethylation and difluorocyclopropanation were achieved with the aid of suitable promotors, such as tetrabutyl­ammonium triphenyl­difluorosilicate (TBAT) or NaI . Despite the cost-effectiveness and versatile chemical behaviors, Me 3 SiCF 3 was usually considered as an inefficient difluorocarbene source for consecutive bond-forming reactions .…”

Aqueous Base Promoted O-Difluoromethylation of Carboxylic Acids with TMSCF2Br: Bench-Top Access to Difluoromethyl Esters

“…disulfide containing 1o produced a 1:1 mixture of 2o and 2o′, with <4% formation of the gem-difluoromethyl dithioacetal (the product of CF 2 insertion into the S−S bond). 20 As stated previously, carboxyl groups can be found in a number of FDA approved drugs and in biologically relevant molecules. To test the applicability of this method on complex molecules, acids 1p−1u were subjected to the reaction conditions (Scheme 3).…”

“…An alternative approach comes in the form of difluorocarbene. Generated from silicon-based reagents, this intermediate has received much recent interest, having been applied to C, − N, B, O, S, Se, and P centers. Considering the abundance of carboxylic acids in nature and in pharmacologically relevant molecules, it is interesting that such an approach has rarely been applied (Figure ) for the generation of difluoromethyl esters, which could prove to be valuable compounds.…”

Chemoselective N- and O-Difluoromethylation of 2-Pyridones, Isoquinolinones, and Quinolinones with TMSCF2Br

“…Particularly, difluoromethylation has emerged as an important reaction paradigm due to the lipophilicity and hydrogen bond donor ability of −CF 2 H, − enabling bioisosteric replacement of commonly encountered functional groups including −OH and −SH . Consequently, nucleophilic, − electrophilic, − and radical − difluoromethylations have been developed. Electrophilic difluoromethylation using difluorocarbene is a popular method for insertion of −CF 2 – into alkenes/alkynes, , as well as C–H, , O–H, S–H, N–H, and P–H bonds.…”