A method for the generation of free radicals from thiazolinium salts upon photocatalytic reduction is described. The thiazolinium salts are generated by treatment with methyl triflate of 2-mercaptothiazolines, which can be readily obtained from alkyl bromides and tosylates via a nucleophilic substitution reaction or by hydrothiolation of alkenes. Silyl enol ethers were used to trap the radicals, furnishing ketones after successive single-electron oxidation and elimination of the silyl cation.

The oxidized form of baicalein (BA) leads to covalent binding with human amyloid proteins. Such adducts hamper the aggregation and deposition of fibrils. A novel reaction of BA with pentylamine (PA) as a model for the lysine side chain is described. This is the first study addressing the atomistic details of a Schiff base reaction with the trihydroxylated moiety of BA. Nuclear magnetic resonance and mass spectrometry approaches clearly indicate the formation of dehydrobaicalein in solution as well as its condensation with PA under aerobic conditions, yielding regioselectively C6‐substituted products. The combined results suggest initial ion pair formation between BA and PA, followed by a redox chain reaction: the initiation by oxygen/air; an o‐quinone‐based chain involving oxidation and reduction steps; and extra off‐chain formation of a doubly oxidized product. These mechanistic details support the anti‐amyloid activity of BA and endorse its trihydroxyphenyl moiety as a pharmacophore for drug‐design studies.

A cross-coupling of acyl chlorides with gem-difluorinated organozinc reagents affording difluorinated ketones is described. In the reaction, acyl chlorides are first treated with potassium dithiocarbamate to generate S-acyl dithiocarbamates, which couple with organozincs in the presence of a copper(I) catalyst.

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