Palladium-Catalyzed Esterification of Aryl Fluorosulfates with Aryl Formates.

An efficient palladium-catalyzed carbonylation of aryl fluorosulfates with aryl formates for the facile synthesis of esters was developed. The cross-coupling reactions proceeded effectively in the presence of a palladium catalyst, phosphine ligand, and triethylamine in DMF to produce the corresponding esters in moderate to good yields. Of note, functionalities or substituents, such as nitro, cyano, methoxycarbonyl, trifluoromethyl, methylsulfonyl, trifluoromethoxy, fluoro, chloro, bromo, methyl, methoxy, N,N-dimethyl, and [1,3]dioxolyl, were well-tolerated in the reactions, which could be kept for late-stage modification. The reactions employing readily available and relatively robust aryl fluorosulfates as coupling electrophiles could potentially serve as an attractive alternative to traditional cross-couplings with the use of aryl halides and pseudohalides as substrates.

Hydroxylation of Aryl Sulfonium Salts for Phenol Synthesis under Mild Reaction Conditions.

Hydroxylation of aryl sulfonium salts could be realized by utilizing acetohydroxamic acid and oxime as hydroxylative agents in the presence of cesium carbonate as a base, leading to a variety of structurally diverse hydroxylated arenes in 47-95% yields. In addition, the reaction exhibited broad functionality tolerance, and a range of important functional groups (e.g., cyano, nitro, sulfonyl, formyl, keto, and ester) could be well amenable to the mild reaction conditions.

Nickel-Catalyzed Direct Cross-Coupling of Unactivated Aryl Fluorides with Aryl Bromides.

A nickel-catalyzed direct cross-coupling of unactivated aryl fluorides with aryl bromides is realized. The one-pot reaction, which avoids the use of preformed and sensitive organometallic reagents, proceeds effectively via C-F bond cleavage at room temperature in THF in the presence of the phosphine ligand and magnesium powder (with or without TMSCl) to produce the desired biaryls in modest to good yields.

Plasma Electrolytic Oxidation of Magnesium Alloy AZ31B in Electrolyte Containing Al2O3 Sol as Additives.

Plasma electrolytic oxidation (PEO) coatings were produced on AZ31B magnesium alloys in alkaline electrolytes with the addition of various concentrations of Al2O3 sols. Effects of Al2O3 sol concentrations on the microstructure, phase composition, corrosion resistance and hardness of PEO coatings were evaluated by scanning electron microscopy (SEM), X-ray diffraction (XRD), microhardness testing and potentiodynamic polarization measurements, respectively. It was revealed that the Al2O3 sol mostly participated in the formation of the ceramic coating and transferred into the MgAl2O4 phase. With the increase of the Al2O3 sol concentration in the range of 0⁻6 vol%, the coating performance in terms of the microstructure, diffraction peak intensity of the MgAl2O4 phase, corrosion resistance and microhardness was improved. Further increase of Al2O3 sol addition did not generate better results. This indicated that 6 vol% might be the proper Al2O3 sol concentration for the formation of PEO coatings.

(Z)-N-[(Z)-3-(2,4-Dimethyl-phenyl-imino)-butan-2-yl-idene]-2,4-dimethyl-aniline.

The asymmetric unit of the title compound, C(20)H(24)N(2), contains one half -mol-ecule which exhibits a crystallographically imposed center of symmetry. The benzene rings are inclined to the 1,4-diaza-butadiene mean plane by 78.3 (2)°.

(E)-N-{(E)-2-[(3,5-Dimethylbiphenyl-4-yl)imino]-acenaphthen-1-yl-idene}-2,6-di-methyl-4-phenyl-aniline.

The title compound, C(40)H(32)N(2), has crystallographic twofold rotation symmetry, with two C atoms lying on the axis. The dihedral angle between the two benzene rings of the 4-phenyl-2,6-dimethyl-phenyl group is 35.74 (17)°. The acenaphthene ring makes an angle of 76.93 (11)° with the benzene ring bonded to the N atom and an angle of 41.53 (13)° with the other benzene ring.