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The styrenated sulfur- and phosphorus-free organic titanate (STAE) was synthesized via an in situ method with soybean oil, diethanolamine, and isopropyl titanate. The tribological and antioxidant behavior of the as-synthesized STAE as an additive in PAO was evaluated by a four-ball test, a rotary oxygen bomb test (ROBT), and differential scanning calorimetry (DSC), and its oxidative stability was estimated through thermogravimetric analysis (TGA). The as-synthesized STAE exhibits excellent antiwear and load-carrying capacities as well as good antiwear synergism with zinc dialkyldithiophosphate (ZDDP) in poly-α-olefin (PAO). STAE in PAO also showed good synergistic antioxidation effects with the traditional additive p,p-(dioctyldiphenylamine (DODPA). This is because STAE can effectively reduce the oxidation rate of DODPA, which was confirmed by the results of Fourier transform infrared spectroscopy (FTIR) and gas chromatography-tandem mass spectrometry (GC/MS).

A room-temperature Ni-catalyzed reductive approach to homocoupling of unactivated primary, secondary, and tertiary alkyl bromides is described. The catalytic system can be easily generated from air-stable and cheap materials and demonstrates broad functional group tolerance, thus allowing facile access to useful dimeric triterpene and lignan-like molecules. Moreover, the dimerization of tertiary bromide 6 efficiently establishes sterically hindered vicinal quaternary carbons (C3a and C3a'), which is a key linkage of intriguing bispyrrolo[2,3-b]indoline alkaloids, thereby enabling us to complete the total syntheses of racemic chimonanthine (9) and folicanthine (10). In addition, this dimerization method can be expanded to the highly stereoselective synthesis of bisperhydrofuro[2,3-b]furan (5a) and the dimeric spiroketal 5b, signifying the involvement of possible radical species.

A Ni(0)-catalyzed intermolecular cross-coupling of various functionalized thiols and aryl iodides has been developed and successfully extended to less explored intramolecular versions, where thioacetates could also be utilized as the strategic surrogate. Air-stable precatalysts, very mild conditions, and an easy protocol allow rapid access to medicinally useful aryl thioethers, as demonstrated in the facile synthesis of (±)-chuangxinmycin as a key step.

Par photolyse, photosensibilise par le dicyano-9,10 anthracene, d'α-benzoyl S,S-dialkyl sulfoniomethanures on obtient intermediairement des α-dimethylsulfonio β-oxo phenethyles. Par transposition de cet intermediaire on obtient principalement des derives de tetrahydro-1,2,3,4 naphtalenones-1, de cyclopropanes et de propiophenones