Hypervalent Iodine Reagent-Promoted Hofmann-Type Rearrangement/Carboxylation of Primary Amides
A novel transformation of primary amides to secondary amides promoted by hypervalent iodine reagents was developed. The hypervalent iodine reagent-mediated Hofmann-type rearrangement generated an isocyanate intermediate, which was subsequently trapped by an in situ generated carboxylic acid from the hypervalent iodine reagent to provide the corresponding secondary amides. This method provided a facile and efficient route for the synthesis of secondary amides from primary amides and also revealed novel reactivities of hypervalent iodine reagents.
Wang, Xia,Yang, Peng,Hu, Bo,Zhang, Qian,Li, Dong
p. 2820 - 2826
(2021/02/01)
Highly chemoselective difluoromethylative homologation of iso(thio)cyanates: Expeditious access to unprecedented α,α-difluoro(thio)amides
The new motif-α,α-difluoromethyl thioamide-has been assembled starting from isothiocyanate (as thioamide precursor) and a formal difluoromethyl-carbanion generated from commercially available TMSCHF2. Upon proper activation of this reagent with
Overcoming inaccessibility of fluorinated imines-synthesis of functionalized amines from readily available fluoroacetamides
Although imines are convenient substrates for the synthesis of functionalized amines, they may be hard to obtain, as in the case of fluorinated imines. To aid in overcoming this issue, we propose a protocol of corresponding amine synthesis from simple fluoroacetic acid-derived amides using Schwartz's reagent.