Bacteroides acidifaciens: Linking dietary fiber to liver health.

While innumerous associative microbiome studies have been published, mechanistic links between the microbiome and host physiology remain much scarcer. In Cell Host & Microbe, Shen et al. report the effect of soluble dietary fibers in alcohol-related liver disease.

Reaction of 2,2,4,4-tetrakis(trifluoromethyl)-1,3-dithiethane with N-vinyl compounds.

The reaction of hexafluorothioacetone dimer (2,2,4,4-tetrakis(trifluoromethyl)-1,3-dithiethane, 1) with vinylamides leads to the rapid formation of [2 + 2] cycloadducts: 4-amino-2,2-bis(trifluoromethyl)thietanes. The reaction proceeds in polar solvents (DMF, DMSO) in the absence of a catalyst at elevated temperature producing the corresponding cycloadducts in 47-86% yield. The reaction of N-vinylimidazole unexpectedly led to the formation of the corresponding 1-(hexafluoroisopropyl)-3-vinyl-1,3-dihydro-2H-imidazole-2-thione (5).

Acid catalyzed cyclodimerization of 2,2-bis(trifluoromethyl)-4-alkoxy-oxetanes and -thietanes. Synthesis of 2,2,6,6-tetrakis(trifluoromethyl)-4,8-dialkoxy-1,5-dioxocanes and 3,3,7,7-tetrakis(trifluoromethyl)-9-oxa-2,6-dithia-bicyclo[3.3.1]nonane.

Treatment of 2,2-bis(trifluoromethyl)-4-R-oxetanes (R = C₂H₅O, n-C₃H₇O, n-C₄H₉O) with BF₃.OEt₂ in CH₂Cl₂ solvent results in spontaneous electrophilic [4 + 4] cyclodimerization with the formation of the corresponding 2,2,6,6-tetrakis(trifluoromethyl)-4,8-dialkoxy-1,5-dioxocanes, isolated in 31-42% yield. The structures of two products (R = C₂H₅O and n-C₃H₇O) were established by single crystal X-ray diffraction.

The first perfluoroacetylacetonate metal complexes: as unexpectedly robust as tricky to make.

First metal complexes containing the perfluoroacetylacetonato ligand have been prepared by the reaction of anhydrous Ln(OAc)3 (Ln = Eu, Tb, Tm) with heptafluoroacetylacetone, optionally in the presence of other ligands Ph3PO, bpy, and PyO.

Selective Reduction of Halopolyfluorocarbons by Organosilicon Hydrides.

It is demonstrated that silicon hydrides can be used for reduction of polyfluorinated halocarbons. For example, the reaction between CF(3)CCl(2)F and excess triethylsilane, catalyzed by benzoyl peroxide, leads to the formation of a mixture containing CF(3)CHClF (major), CF(3)CH(2)F, and ClSi(C(2)H(5))(3). On the other hand, the reaction of chlorofluoroalkanes, containing an internal -CCl(2)- group readily proceeds with reduction of both chlorines, leading to compounds such as (CF(3))(2)CH(2) and CF(3)CH(2)C(2)F(5).

Selective Epoxidation of Olefins by Perfluoro-cis-2,3-dialkyloxaziridines(1).

Alkyl-substituted olefins are epoxidized by perfluoro-cis-2,3-dialkyloxaziridines under particularly mild conditions. Electron deficient substrates (e.g.