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The poly(diphenylamine) derivative (PDPA) as amine antioxidant was synthesized via diphenylamine, styrene, and formaldehyde. The steps of the synthesis were discussed in detail, and the structure of PDPA was fully characterized with multiple analysis techniques. Furthermore, the anti-oxidative properties of PDPA were evaluated through oxidation–corrosion tests and differential scanning calorimetry. It was found that PDPA significantly improved the oxidation stability of base oils, especially pentaerythritol ester when it was added at concentrations of only 0.5 wt % to 0.8 wt %. Thermogravimetric analysis shows that anti-oxidation behavior of PDPA is better than traditional additive p, p-dioctylphenylamine. The synthesized PDPA antioxidant is a potential alternate additive in high-temperature conditions.

A new I2-mediated iodobenzannulation of yne-allenones has been established, enabling breaking/rearranging of C≡C bonds to selectively access 4-iodonaphthalen-1-ols with generally good yields. The resulting 4-iodonaphthalen-1-ols could serve as a new and reliable coupling reagent, which further reacted with H2O under the oxygen conditions to generate unexpected 1,2-carbonyls with good yields through Pd-catalyzed deiodinated carbonylation, whereas employment of benzene-1,2-diamine as the nucleophile rendered 3-(quinoxalin-2-yl)naphthalen-1-ols through Pd-catalyzed [4 + 2] heterocyclization. On the basis of the controlled experiments, the mechanism for forming 1,2-carbonyls was proposed, including an oxidative addition, 1,3-palladium migration, reductive elimination, and oxidative dehydrogenation sequence.

A novel method of catalytic thermometric titration has been developed for the determination of the acidity of oils using titration with KOH in isopropanol as titrant. The amounts of oil, concentration and delivery rate of titrant, volumes and types of thermometric end-point indicator were investigated. The results show that mixture of acetone and chloroform used as indicator exhibits strongly exothermic effects to reflect end point obviously. The results obtained from the thermometric titration have good agreement with standard potentiometric and visual titration methods. The procedure is fast, easy to use, accurate, and highly reproducible to measure lower acidity in coloured oils. It is very suitable for the routine process and quality control of many types of oils.

A new hydrofunctionalization/bicyclization of C(sp3)-tethered 1,7-enynes toward benzo[a]fluoren-5-ones with good to excellent yields has been developed by using Iron(III)/PhSiH3 system as a hydride donor. This protocol involves a reductive 1,7-enyne-carboannulation cascade, leading to C(sp3) H and C C bond-forming events to rapidly build up tetracarbocyclic complexity. A wide range of functional groups relative to 1,7-enyne substrates were tolerated well under mild neutral-redox conditions.

A first atom-economic [2 + 2] cycloaddition/1,6-conjugate addition cascade of yne-allenones with C-nucleophiles including 1,3-dicarbonyls and α,α-dicyanoolefins under base-promoted conditions has been established, enabling the direct construction of C(sp3)–C(sp3) bonds to generate cyclobuta[a]naphthalen-1-ols with generally good yields. These resulting products have a cyclobutene unit that contains both an aryl and alkyl group.