Synthesis of the monomeric counterpart of Marinomycin A and B.

The synthesis of polyketide natural products has been a captivating pursuit in organic chemistry, with a particular focus on selectively introducing 1,3-polyol units. Among these natural products, Marinomycins A-D have garnered substantial interest due to their exceptional structural features and potent cytotoxicity. In this paper, we present a novel approach for synthesising the monomeric counterparts of Marinomycin A and B. Our method employs a previously established iterative cycle in conjunction with a standardised polyketide building block. Through this strategy, we showcase a promising pathway towards total and partial syntheses of these intriguing natural products.

Oxidation of Alcohols in Continuous Flow with a Solid Phase Hypervalent Iodine Catalyst.

One of the most useful transformations in the synthetic chemist arsenal is the oxidation of alcohols to their corresponding carbonyl congeners. Despite its seemingly straightforward nature, this transformative reaction predominantly relies on the use of metals or hazardous reagents, making these processes highly unsustainable. To address this challenge, we have developed a sustainable metal-free method for the oxidation of alcohols in continuous flow. Using a solid phase hypervalent iodine catalyst and nBu4HSO5 as a phase transfer catalyst and co-oxidant, primary and secondary alcohols were selectively oxidized to the corresponding carbonyl motifs. This operationally simple continuous-flow set-up is highly robust (15 cycles run without significant catalyst leaching or loss of reaction efficiency), uses green solvents, such as acetonitrile or acetic acid, and is readily scalable.

Light-Mediated Formal Radical Deoxyfluorination of Tertiary Alcohols through Selective Single-Electron Oxidation with TEDA2+.

The synthesis of tertiary alkyl fluorides through a formal radical deoxyfluorination process is described herein. This light-mediated, catalyst-free methodology is fast and broadly applicable allowing for the preparation of C-F bonds from (hetero)benzylic, propargylic, and non-activated tertiary alcohol derivatives. Preliminary mechanistic studies support that the key step of the reaction is the single-electron oxidation of cesium oxalates-which are readily available from the corresponding tertiary alcohols-with in situ generated TEDA2+. (TEDA: N-(chloromethyl)triethylenediamine), a radical cation derived from Selectfluor®.