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A one-pot alkylation-halogenation of ketosulfoxonium ylides in the presence of alkyl halides is described. The method furnishes several gem-difunctionalized haloketones (an alkyl and F, Cl, Br, or I) in good yields. Replacing alkyl halides with a mixture of electrophilic halogen species and various halide anions led to gem-dihalogenated ketones containing a combination of the same or two different halogens. Kinetic isotopic effects as well as reaction kinetic experiments give insight to the mechanism of these reactions.

A new visible-light-promoted reaction between aryldiazoacetates and 1,3-diketones allows good yields and selectivities for C–C bond insertions, leading to the corresponding 1,4-dicarbonyl compounds. This transformation is straightforward and highly practical. It tolerates air and moisture and does not require the use of any metals. Mechanistic investigations support the involvement of a key cyclopropanol intermediate derived from an intramolecular rearrangement.

Two new visible-light-mediated strategies are described starting from aryldiazoacetates. The first approach describes their reaction with azides to afford the corresponding imines, and then reaction with aryldiazoketones produces alkyl 2carboxylate-2,3,3-trisubstituted β-lactams. The second approach describes the reaction with sulfoxides to afford the corresponding sulfoxonium ylides, followed by reaction with aryldiazoketones to produce 5-alkoxy-2,2,4-trisubstituted furan-3(2H)-ones. These protocols take advantage of the photolysis of aryldiazoacetates and the photochemically promoted Wolff rearrangement of aryldiazoketones.

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Uma reação simples e seletiva para a preparação de fenóis iodados foi desenvolvida e derivados fenólicos contendo substituintes eletroretiradores foram iodados em rendimentos muito bons sob condições relativamente brandas.A simple and selective reaction for the preparation of iodinated phenols was developed and phenol derivatives containing electron withdrawing groups were iodinated in very good yields under relatively mild conditions.

An eco-friendly and metal-free protocol to perform O–H insertion reactions, using only 0.3 mol% of a recyclable silica-immobilized BrØnsted acid is described.

A blue light-promoted reaction between aryldiazoacetates and different nucleophiles has been developed in the presence of THF (and other cyclic ethers) as solvent, allowing the incorporation of these three elements...