Stereoselective Synthesis of (Z)‐β‐Enamido Triflates and Fluorosulfonates from N‐Fluoroalkylated Triazoles

Abstract

N-Fluoroalkylated 1,2,3-triazoles in the presence of triflic acid or fluorosulfonic acid underwentacascade reactionc onsisting of triazole protonation, ring opening, nitrogene limination, sulfonate addition, HF elimination, and hydrolysis to furnish novel trifluoromethanesulfonyloxy-or fluorosulfonyloxy-substituted enamides, respectively,i nahighly stereoselective fashion. The vinyl triflates underwent cross-coupling reactions to av ariety of substituted enamidesa nd serve as sourceso ft he aminovinyl cations. In reactions with triflic acid, electron-rich triazoles afforded2 -fluoroalkylated oxazoles. 2( CzechRepublic) [c] V. Motornov HigherChemical College, D. I. Mendeleev Universityo fthe Chemical Technologyo fRussia, Miusskaya sq.9,Moscow 125047 (Russia) Supporting information and the ORCID identification number(s) for the author(s) of this articlecan be found under: https://doi.

Synthesis, Stability and Reactivity of α‐Fluorinated Azidoalkanes

“…In the presence of a Rh II catalyst under microwave heating, triazoles 11 eliminate nitrogen and form rhodium carbenoids, which undergo a variety of transannulation reactions giving nitrogen heterocycles, such as N‐fluoroalkyl pyrroles, imidazoles, azepines and other . In the presence of triflic acid at room temperature, β‐enamido triflates form from triazoles 11 …”

Haloalkenyl Imidoyl Halides as Multifacial Substrates in the Stereoselective Synthesis of N‐Alkenyl Compounds

“…In 2019 we showcased a new type of reactivity specific to N ‐fluoroalkyl triazoles under superacidic conditions. N ‐Fluoroalkyl triazoles underwent a cascade transformation mediated by triflic or fluorosulfonic acids to β‐enamido triflates or fluorosulfonates, respectively [54] . The reaction sequence consists of a ring opening, nitrogen elimination, sulfonate addition and HF elimination leading to an unstable imidoyl fluoride, which reacted with air moisture to furnish the final enamides.…”

Ligand-dependent stereoselective Suzuki–Miyaura cross-coupling reactions of β-enamido triflates

“…B: Ligand-controlled stereoselective synthesis of β,β-diaryl-substituted enamides. pling reactions with retention of configuration on the double bond and served as valuable starting materials for the synthesis of functionalized β,β-disubstituted enamides (Scheme 1A) [21,23].…”

“…Recently, we have reported a triflic acid-mediated reaction of N -fluoroalkyl-1,2,3-triazoles leading to ( Z )-β-enamido triflates [ 21 ] and Lewis acid-mediated reaction to ( Z )-β-enamido fluorides [ 22 ] and halovinyl imidoyl halides [ 23 ]. In addition, Li and co-workers extended the scope of accessible ( Z )-β-enamido triflates by denitrogenative reaction of N 1- H -1,2,3-triazoles in the presence of acyl halides and sodium triflate [ 24 ].…”

“…In addition, Li and co-workers extended the scope of accessible ( Z )-β-enamido triflates by denitrogenative reaction of N 1- H -1,2,3-triazoles in the presence of acyl halides and sodium triflate [ 24 ]. These enamido triflates and halides were found to undergo cross-coupling reactions with retention of configuration on the double bond and served as valuable starting materials for the synthesis of functionalized β,β-disubstituted enamides ( Scheme 1A ) [ 21 , 23 ].…”