Visible-light promoted cross-coupling of ethyl iododifluoroacetate with silyl enol ethers for the synthesis of β-fluoroenones via noncovalent interactions

Visible‐Light Promoted Radical Fluoroalkylation of O‐ and N‐Substituted Alkenes

“…Iododifluoroacetic ester ex- hibited a very high activity, apparently due to the effect of the carbonyl group, and its reaction with enol ethers having SiEt 3 group proceeded without photocatalyst in DMF. [41] Based on the spectrophotometric measurements, it was proposed that the electron donor-acceptor (EDA) complex is formed between DMF and iododifluoroacetate, and that its absorption band extends into the visible region, allowing the use of blue light. In less donating solvents such as MeCN, THF, DCE the reaction works much slower or does not work at all.…”

“…[63] Primary products of fluoroalkylation of enol ethers may be involved in subsequent transformations relying on the electrophilic reactivity of the carbonyl group. The propensity of the β-fluoroketones to undergo elimination of hydrogen fluoride [41] opens opportunities for the synthesis of heterocyclic compounds. For example, three-component coupling of silyl enol ethers, perfluorinated alkyl iodides and amidinium salts catalyzed by Eosin Y afforded pyrimidines containing a perfluorinated substituent (Scheme 13).…”

Acetone Serving as a Solvent and Interaction Partner Promotes the Direct Olefination of N-Tosylhydrazones under Visible Light

“…In contrast, using the solvent as the interaction partner to promote the reaction is a highly desirable method, which makes NCI-mediated reaction more sustainable and attractive. 10,24,25 The intramolecular synthesis of olefins from ketones continues to attract extensive attention because the synthesis of natural products or other important fine chemicals often requires the installation of double bond without adding carbon. 26−28 The most traditional and robust methods to prepare olefins via the intramolecular carbon−carbon double bond formation include Shapiro and Bamford−Stevens reactions, which serve as highly convenient and robust strategies.…”

“…Over the last few decades, visible-light-mediated organic synthesis has drawn great attention as a powerful and sustainable synthetic method. − Among diverse photochemical approaches, the formation of noncovalent interactions (NCIs) to trigger organic transformations under visible-light irradiation becomes a prevalent strategy due to its sustainable properties. − Although the individual substrate does not have absorption under the visible-light region, the formed complex in the solution enables the red shift and further activates by visible-light irradiation, thereby facilitating the reaction process. − Compared with the employment of external photocatalysts and oxidants, NCI-mediated transformations, including the electron-donor complex-mediated synthesis, enable the absorption of the energy from the visible light and further undergo the reaction process. − Generally, the external substance is necessary to add as an interaction partner, thereby sacrificing the atom economy of the reaction. In contrast, using the solvent as the interaction partner to promote the reaction is a highly desirable method, which makes NCI-mediated reaction more sustainable and attractive. ,, …”

Transition metal-free electrochemical fluorotrifluoromethylation of Styrenes

“…S2†), the pure p -bromostyrene-derived product could not be obtained, which may be caused by its instability in column chromatography. 10 For the latter, the p-tert -butylstyrene-derived product was formed in 84% GC yield (Fig. S3†), while the accurate isolated yield was not obtained due to the volatility.…”