Hydrotrifluoromethylation of Unactivated Alkenes and Alkynes Enabled by an Electron-Donor–Acceptor Complex of Togni’s Reagent with a Tertiary Amine

Abstract

An electron-donor-acceptor (EDA) complex between Togni's reagent and a tertiary amine has been introduced. The existence of this EDA complex was supported by NMR titration experiments. The hydrotrifluoromethylation of unactivated aliphatic alkenes and alkynes enabled by this EDA complex has also been developed. This hydrotrifluoromethylation protocol is operationally simple and promoted by a tertiary amine.

Supramolecular Aggregation of Perfluoroorganyl Iodane Reagents in the Solid State and in Solution

“…The different solvent effects could be exploited to help enhance or suppress a particular reaction pathway. Clean electrophilic R F + reactivity can be expected to be prominent in acceptor solvents, whereas reactions including R F radicals seem to be more pronounced in donor solvents . The different aggregation modes in solution also give insights into the possible preorganization of the reagent and substrate in solution through σ donation, π donation, or hydrogen bonding.…”

“…Moreover, acid reagent 1 can be activated by nucleophiles such as iodide and tertiary amines . In the latter, the existence of a distinct Lewis acid–base adduct was supported by 1 H NMR titrations, but the formation constant of such an adduct with N ‐methylmorpholine was determined to be quite low (3.83 L/mol) . In contrast, our group found that alcohol reagent 4 forms more stable adducts with Lewis acids through the oxygen atom as a nucleophilic functionality.…”

“…In this case, a sharp 19 F NMR signal was obtained for the compound in CDCl 3 , whereas the signal of the compound in CD 3 CN was broadened owing to the dynamic exchange of the coordinated solvent molecules. Moreover, acid reagent 1 can be activated by nucleophiles such as iodide and tertiary amines . In the latter, the existence of a distinct Lewis acid–base adduct was supported by 1 H NMR titrations, but the formation constant of such an adduct with N ‐methylmorpholine was determined to be quite low (3.83 L/mol) .…”

“…[22] In the latter, the existence of a distinct Lewis acid-base adduct was supported by 1 H NMR titrations, but the formation constant of such an adduct with N-methylmorpholine was determined to be quite low (3.83 L/mol). [22] In contrast, our group found that alcohol reagent 4 forms more stable adducts with Lewis acids through the oxygen atom as a nucleophilic functionality. For instance, the formation constant of a 1:1 adduct with ZnBr 2 is 234(25) L/mol.…”

Donor–Acceptor Complex Enables Alkoxyl Radical Generation for Metal‐Free C(sp3)–C(sp3) Cleavage and Allylation/Alkenylation

“…[5] Donor-acceptor complexes are molecular complexes resulting from the association of an electron donor molecule (D) with an electron acceptor molecule (A), which generally demonstrate partial or total electron transfer from Dt oA upon irradiation (Scheme 1b). [7,8] TheN ADH (the reduced form of nicotinamide adenine dinucleotide) is known to form the donor-acceptor complex when bound to the enzyme, [9] however its synthetic analog Hantzsch ester (HE) has not been reported for donor-acceptor complex formation. [7,8] TheN ADH (the reduced form of nicotinamide adenine dinucleotide) is known to form the donor-acceptor complex when bound to the enzyme, [9] however its synthetic analog Hantzsch ester (HE) has not been reported for donor-acceptor complex formation.…”