Sulfones in heterocyclic synthesis: advances in the chemistry of phenyl sulfonylacetophenone

Developments of pyridodipyrimidine heterocycles and their biological activities

The entitled review aimed to assemble and highlight the synthetic approaches and biological aspects of heterocycles with pyridodipyrimidine motifs. The recent synthetic approaches were categorized according to the accomplishments of the approaches under catalyst or catalyst-free conditions. The topic involved the synthesis of substituted tricyclic systems and spirocyclic systems. The present study offered an overview of the recent literature in addition to a scope of the preceding literature. The proposed mechanisms of the varied target products were discussed. Pyridodipyrimidine displayed potential and privileged cytotoxic, antioxidant, and antimicrobial performances. The competitions, challenges, and prospects are also deliberated.

Synthetic strategies of heterocycle-integrated pyridopyrimidine scaffolds supported by nano-catalysts

Nano-catalysts are of special character for the synthesis of organic molecules with high efficiency, and exceptional physicochemical properties. The objective of this study was to present an overview of the literature reports concerning the synthetic strategies supported by nano-catalysts and the biological features of heterocycle-integrated pyridopyrimidine scaffolds. The basic topics include the strategies that were adopted to prepare pyrido[2,3-d]pyrimidines and pyrido[1,2-a]pyrimidines. The synthesis of pyrido[2,3-d]pyrimidines was attained through two-, three-, or four-component reactions. The synthesis of spirocyclic systems, including spiro[indoline-pyridopyrimidine] derivatives and arylation reactions, was investigated. The anticipated mechanisms of the diverse target products, in addition to the preparation of the nanocatalysts, were scrutinized. The privileged antimicrobial characteristics, challenges, literature overview, and future prospectives were consistently investigated.

Divergent upgrading pathways of sulfones with primary alcohols: nickel-catalyzed α-alkylation under N2 and metal-free promoted β-olefination in open air

We report here our findings on the diverse reaction results of sulfones and alcohols. In the presence of NiCl₂/P(t-Bu)₃ and under a N₂ atmosphere, α-C-alkylation of sulfones with alcohols occurs through a borrowing-hydrogen mechanism; when the reaction was carried out in the open air without nickel, the product was not the predicted α,β-unsaturated sulfone, but the β-alkenyl sulfone, which is a useful building block in organic synthesis.

Chemoenzymatic Oxosulfonylation-Bioreduction Sequence for the Stereoselective Synthesis of β-Hydroxy Sulfones

A series of optically active β-hydroxy sulfones has been obtained through an oxosulfonylation-stereoselective reduction sequence in aqueous medium. Firstly, β-keto sulfones were synthesized from arylacetylenes and sodium sulfinates to subsequently develop the carbonyl reduction in a highly selective fashion using alcohol dehydrogenases as biocatalysts. Optimization of the chemical oxosulfonylation reaction was investigated, finding inexpensive iron(III) chloride hexahydrate (FeCl₃  ⋅ 6H₂ O) as the catalyst of choice. The selection of isopropanol in the alcohol-water media resulted in high compatibility with the enzymatic process for enzyme cofactor recycling purposes, providing a straightforward access to both (R)- and (S)-β-hydroxy sulfones. The practical usefulness of this transformation was illustrated by describing the synthesis of a chiral intermediate of Apremilast. Interestingly, the development of a chemoenzymatic cascade approach avoided the isolation of β-keto sulfone intermediates, which allowed the preparation of chiral β-hydroxy sulfones in high conversion values (83-94 %) and excellent optical purities (94 to >99 % ee).

Recent progress in the chemistry of β-aminoketones

The current study highlighted the significance of β-aminoketones as privileged biologically active molecules, recent synthetic strategies, and synthetic applications.

A new method for C(sp2)-H sulfonylmethylation with glyoxylic acid and sodium sulfinates

We herein describe a C4 sulfonylmethylation of pyrazol-5-amines with glyoxylic acid and sodium sulfinates. The reaction only needed to add water as the solvent, and it featured mild reaction condition,...

Electrochemical Synthesis of β-Ketosulfones from Switchable Starting Materials

A synthesis of β-ketosulfones via sulfination of aryl methyl ketones and aryl acetylenes with sodium sulfinates under mild electrochemical conditions, in moderate to good chemical yields, is described. In particular, an electrochemical sulfination reaction of alkynes with sulfinate salts has never been explored. An environmentally friendly characteristic of this reaction is that it uses electricity as a valuable energy source for electrochemical synthesis of β-ketosulfones. This strategy is more convenient and practical compared to previous approaches.

Palladium-catalyzed three-component tandem reaction of sulfonyl hydrazones, aryl iodides and allenes: highly stereoselective synthesis of (Z)-α-hydroxymethyl allylic sulfones

Sulfonyl hydrazones have been identified as an excellent sulfonyl anion surrogate in the tandem reaction with aryl iodides and allenes for the synthesis of functionalized (Z)-allylic sulfones.