Sulfur Assisted Tandem Electrophilic Fluorinative Deacylation: Synthesis of α-Fluoro β-Ketosulfides

Efficient Monofluoroalkylation of Thiophenols or Phenols with α-Bromo-α-Fluoroketones under Mild Conditions

An efficient nucleophilic substitution reaction between α-bromo-α-fluoroketones and thiophenols or phenols is reported for the synthesis of α-fluoro-β-ketosulfides or α-fluoro-β-ketone ethers in yields ranging from 78–93%. This method exhibits good functional group tolerance and a broad scope of nucleophilic substrates, including natural phenolic compounds.

KI-catalyzed C-S bond formation via an oxidation relay strategy: efficient access to various α-thio-β-dicarbonyl compounds

An efficient and practical methodology to obtain α-thio-β-dicarbonyl compounds was presented under alkaline conditions via potassium iodide (KI) catalysis; various symmetrical/unsymmetrical 1,3-dicarbonyl compounds were obtained under an aerobic atmosphere in moderate to excellent yields, with good functional group tolerance. Notably, a widely used anti-inflammatory drug butazodine could be modified with our protocol, even on a gram scale.

Oxidative Difluoromethylation of Tetrahydroisoquinolines Using TMSCF2SPh: Synthesis of Fluorinated Pyrrolo[2,1-a]isoquinolines and Benzo[a]quinolizidines

An efficient C1-difluoromethylation of tetrahydroisoquinolenes was achieved using TMSCF₂SPh as a difluoromethylating agent and 2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (TEMPO⁺BF₄^-) as an oxidant. The process provides an access to a variety of C1-difluoro(phenylsulfanyl)methylated tetrahydroisoquinoline adducts in good yields. These adducts were employed as key precursors for preparing fluorinated pyrrolo[2,1-a]isoquinoline and benzo[a]quinolizidines.