The organocatalyzed aerobic oxidation of aldehydes to acids was reproduced from the original report. In- and ex-situ analysis of the reaction mixture as the function of time reveals that, unlike the claim in the publication, the aerobic oxidation of aromatic and aliphatic aldehydes leads predominantly to the formation of peracids. The latter are transformed into the corresponding carboxylic acids during the workup procedure. The buildup of peracids in solution poses safety problems that should not be overlooked. This finding has also an influence on the way new catalysts are investigated to improve this reaction as well as on aerobic aldehyde-mediated co-oxidation.

We recently reported (J. Catal., 2019, 372, 226-244) that a structure/activity correlation exists in Pd/C catalysts for myrcene hydrogenation, which integrates the Pd dispersion, and the surface concentration of oxygen...

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The preparation of alpha-hydroxyketones derived from fatty acid derivatives has been reported under homogeneous and heterogeneous conditions.

Aldrich, Alfa Aesar and TCI. All reagents were used as received from the chemical company without further purification, excepted for aniline and nitrobenzene which were distilled prior to use. Pd/C (5%) on activated carbon, reduced and dry (Escat 1431) and all the supported catalysts were purchased from Strem Chemicals and Sigma-Aldrich.1 H NMR and 13 C NMR spectra were recorded on a BRUKER DRX 300 or BRUKER ALS 300 ( 1 H 300 MHz, 13 C 75 MHz) in CDCl 3 (except when mentioned) and chemical shifts are given in ppm. J values are given in Hertz (Hz). Abbreviations are defined as follows: br = broad singlet, s = singlet, d = doublet, dd = doublet of doublets, t = triplet, q = quadruplet, m = multiplet.IR spectra were recorded on a Spectro Nicolet IS10 Smart ITR with an ATR diamond.The HRMS-ESI mass spectra were recorded in positive-ion mode on a hybrid quadrupole time-of-flight mass spectrometer (MicroTOFQ-II, Bruker Daltonics, Bremen) with an Electrospray Ionization (ESI) ion source. The flow of spray gas was at 0.6 bar and the capillary voltage was 4.5kV. The solutions were infused at 180µL/h in a mixture of solvents (methanol / dichloromethane / water 45/40/15). The mass range of the analysis was 50-1000m/z and the calibration was done with sodium formate.The HRMS-CI (Chemical Ionization) and HRMS-EI (Electron Ionization) mass spectra were recorded on a high resolution double-focusing (reversed Nier-Johns B/E geometry) mass spectrometer (ThermoFinnigan MAT95XL, Bremen, Germany) equipped with a chemical ionization (CI) and an electron ionization (EI) ion sources. The reagent gas for the CI was isobutane and the calibration for high resolution mass spectra was done with perfluorotrybutylamine (FC43). For the EI an electron energy of 70eV was used and the calibration was done with perfluorokerozene (PFK).The GC-MS analysis were performed on a Focus GC (Thermo Electron Corporation, Bremen, Germany) equipped with a DB-5MS capillary column (30m, 0.25mm i.d, 0.25µm film thickness) and a DSQ mass spectrometer as a detector (Thermo Electron corporation, Bremen, Germany). The carrier gas was helium, at a flow rate of 1 mL/min. Column temperature was initially 70°C for 2 min, then gradually increased to 310°C at 15°C/min and finally kept at 310°C for 10min. The injector temperature was 220°C and the transfer line temperature was 280°C. For GC-MS detection an electron ionization system was used with electron energy of 70 eV, and the mass analyzer was a simple quadrupole. S3 Dehydrogenative alkylation of α-tetralone with amines (A):In a sealed tube under argon, 3 mmol of α-tetralone derivative were added to 15 mmol of amine. Next, 64 mg of Pd/C (5%) (0.03 mmol, 1 mol%) were added to the mixture, under an inert argon atmosphere. The medium was stirred at 130 °C for 16-36 h at 800 rpm, depending on the substrate. Thereafter, the crude was dissolved in a mixture of CH 2 Cl 2 and CH 3 OH and filtered off (Millipore Durapore filter 0.01 µm).The solvents were evaporated under reduced pressure and the crude product was finally purifi...

Dehydrogenative oxidation of vicinal alcohols catalyzed by a commercially 64 wt.% Ni/SiO catalyst leads to the formation of α-hydroxyketone. This first step was developed without additional solvent according to two protocols: "under vacuum" or "with an olefin scavenger". The synthesis of ketols was carried out with good conversions and selectivities. The recyclability of the supported nickel was also studied. Acyloin was then cleaved with oxidative reagent "formic acid/hydrogen peroxide", which is cheap and can be used on a large scale for industrial oxidation processes. The global yield of this sequential system was up to 80 % to pelargonic acid and azelaic acid monomethyl ester without intermediate purification. By treating the acyloin intermediate with hydroxylamine, nitriles were obtained with a good selectivity.

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