Catalyst-Free Arylation of Tertiary Phosphines with Diaryliodonium Salts Enabled by Visible Light

The visible-light-induced arylation of tertiary phosphines with aryl(mesityl)iodonium triflates to produce the quaternary phosphonium salts occurs under mild, metal, and catalyst-free conditions. Photo-excited EDA complexes between diaryliodonium salts and phosphines supposedly enable this transformation, which is difficult to achieve through the traditional ground-state reactions. Demonstrating high functional group tolerance, broad scope, and complete selectivity of the aryl group transfer, the method is particularly compatible with sterically congested phosphines, which are challenging under metal-based catalytic methods.     

Phosphorylation of pyridoxal azomethines. Synthesis of phosphorus containing azomethines and furopyridines

New O-phosphorylated pyridoxal derivatives have been synthesized through the reaction of azomethines with Р^V acid chlorides. 2-Chloro-2-thioxo-5,5-dimethyl-1,3,2-dioxaphosphinanes and diethylchlorothiophosphate have been employed as phosphorylating agents. Regardless of the nature of the phosphorylating agent, the reaction is regioselective at phenolic hydroxyl group. The structure of final products is determined by the nature of the substituent at the nitrogen atom. If R is alkyl or cycloalkyl group, the products of the reaction represent phosphorylated pyridoxal imines, whereas phosphorylated furopyridines are formed in the case R is aryl substituent.     

Syntheses of chiral fused 4,5-diazafluorene–bis(nopinane) derivatives

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Effective bimetallic composite catalysts for the synthesis of arylated furans and thiophenes in aqueous media

Chemistry of Heterocyclic Compounds - N-(4,6-Dimethylpyrimidin-2-yl)-5-phenylisoxazole-3-carboxamide was used as a ligand for obtaining bimetallic boron-containing heterogeneous catalysts...     

α-Diphenylphosphino-N-(pyrazin-2-yl)glycine as a ligand in Ni-catalyzed ethylene oligomerization

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Bidentate Phosphanyl- and Arsanylboranes

A new class of neutral bidentate ligands with pnictogenyl-functional sites has been obtained. The reaction of tmeda⋅(BH₂I)₂ ( 1 , tmeda=tetramethylethylendiamine) with different phosphanides yields the corresponding bidentate phosphanylboranes tmeda⋅(BH₂PH₂)₂ ( 2 a ), tmeda⋅(BH₂PPh₂)₂ ( 2 b ), and tmeda⋅(BH₂tBuPH)₂ ( 2 c ). This reaction strategy could be further extended to synthesize the first bidentate arsanylborane tmeda⋅(BH₂AsPh₂)₂ ( 3 ). Depending on the substituents on the phosphorus, these compounds form different Au^I complexes, to build either polymeric tmeda⋅(BH₂PH₂AuCl)₂ ( 4 a ), or monomeric tmeda⋅(BH₂PPh₂AuCl)₂ ( 4 b ) products. These compounds form also neutral oligomeric group 13/15 chain-like molecules by coordination to a boron moiety such as tmeda⋅(BH₂PH₂BH₃)₂ ( 5 a ) and tmeda⋅(BH₂AsPh₂BH₃)₂ ( 5 b ). DFT calculations provide insight into the differences between the syntheses of mono- and bidentate pnictogenylboranes.     

Separation technique based on electrophoresis,chromatography and magnetism phenomena: the migration time and peak broadening

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Trimetallic NiCoM catalysts (M = Mn,Fe, Cu) for methane conversion into synthesis gas

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Copper Causes Regiospecific Formation of C4F8‐Containing Six‐Membered Rings and their Defluorination/Aromatization to C4F4‐Containing Rings in Triphenylene/1,4‐C4F8I2 Reactions

The presence of Cu in reactions of triphenylene (TRPH) and 1,4‐C₄F₈I₂ at 360 °C led to regiospecific substitution of TRPH ortho C(β) atoms to form C₄F₈‐containing rings, completely suppressing substitution on C(α) atoms. In addition, Cu caused selective reductive‐defluorination/aromatization (RD/A) to form C₄F₄‐containing aromatic rings. Without Cu, the reactions of TRPH and 1,4‐C₄F₈I₂ were not regiospecific and no RD/A was observed. These results, supported by DFT calculations, are the first examples of Cu‐promoted 1) regiospecific perfluoroannulation, 2) preparative C?F activation, and 3) RD/A. HPLC‐purified products were characterized by X‐ray diffraction, low‐temperature PES, and ¹H/¹⁹F NMR.