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The photoinduced, multicomponent reaction of α-diazoketones, silanols, and isocyanides affords α-silyloxy acrylamides, formally derived from α-keto amides. The presence of a secondary amido group makes classic preparative methods for silyl enol ethers unfeasible in this case, while the mild conditions required by this photochemical approach allow their synthesis in good yields; moreover, the general structure can be easily modified by varying each component of the multicomponent reaction. Fine-tuning of the reaction conditions (i.e., solvents, radiation, additives) can be exploited to obtain complete Z selectivity. The reactivity of this overlooked class of silyl enol ethers has been investigated, and features that could pave the way to new applications have been found.

The crucial structural motive in viral protease inhibitors such as atazanavir and darunavir is a chiral aminoalcohol structure. The structure is generally introduced during the synthesis of the protease inhibitor via an α-chloroketone intermediate. The α-chloroketone can be synthesized in a multistep sequence from naturally occurring l-phenylalanine. Herein, we report a onepot synthesis of an α-chloroketone starting from N-Boc-l-phenylalanine in a novel type of “tube-in-flask” semi-batch diazomethane generator. Activation of the amino acid to the mixed anhydride was carried out in the flask, while diazomethane was generated from in situ formed N-nitroso-N-methylurea within a gas-permeable tubing contained inside the flask. The diazomethane diffused through the gas-selective membrane into the flask, and reacted with the anhydride to the diazoketone (Arndt—Eistert reaction). The addition of aqueous hydrogen chloride provided the α-chloroketone and destroyed any excess of diazomethane. The desired product wa...

This is the final peer-reviewed manuscript accepted for publication in ChemPhotoChem Citation of the published version is: ChemPhotoChem 2018, 2, 847-850

An Ugi multicomponent reaction with chiral cyclic amino acids, benzyl isocyanide and cyclic ketones (or acetone) has been exploited as key step for the generation of peptidomimetics. After a straightforward set of elaborations, the peptidomimetics were converted into polycyclic scaffolds displaying two orthogonally protected secondary amines. Libraries of compounds were obtained decorating the molecules through acylation/reductive amination reactions on these functional groups.

The combination of multicomponent approaches with light-driven processes opens up new scenarios in the area of synthetic organic chemistry, where the need for sustainable, atom- and energy-efficient reactions is increasingly urgent. Photoinduced multicomponent reactions are still in their infancy, but significant developments in this area are expected in the near future.

The recently discovered photoinduced three-component reaction of diazo ketones, carboxylic acids, and isocyanides can be efficiently performed under continuous-flow conditions with consequential advantages in terms of selectivity and productivity. The investigation of the flow process and the determination of its sustainability are discussed in detail. This multicomponent reaction affords stereodefined captodative olefins, useful as synthons in organic chemistry.

The synthesis of the title compounds in an operational simple reaction from a variety of diazoketones, isocyanides and carboxylic acids is presented.

We report a straightforward approach to synthesize 2-acyloxyacrylamides, which are useful synthons in organic synthesis. This involves a photoactivated multicomponent reaction, performed both in batch and under continuous flow conditions. This process affords the desired compounds in a stereoselective fashion from readily available starting materials in one step, without the aid of metal catalysis. This paper illustrates the preliminary work, the extensive experiments carried out to understand the limitations of the approach, and the optimization of the conditions for the synthesis of these particular captodative olefins.

The photoinduced three-component reaction between diazoketones, carboxylic acids and isocyanides is reported.

The photoinduced three-component reaction between diazoketones, carboxylic acids and isocyanides is reported.