Activated enol ethers derived from esters or the dinitrile of malonic acid, or from pentane-2,4-dione were treated with hydrazine hydrate. The structures of the obtained products - pyrazoles 5 - were studied with a focus on tautomerism and supramolecular structure. A reverse addition of the reagents led to the isolation of two novel products, namely bis-enehydrazines 6 with an unsymmetrical arr...

The coupling of arylboronic acids with electron-deficient nitroarenes was realized for the first time by using a rhodium(I) catalyst under an air atmosphere, achieving unsymmetrical diaryl ethers with yields ranging from poor to good. From a deuterium labeling experiment, the oxygen atom is derived from ambient water. The efficiency of this reaction was demonstrated by its compatibility with fl...

Herein we describe a new method, enabling the synthesis of highly functionalized 1,4-diketones that are readily differentiated as monosilylenol ethers under Brønsted acid catalysis. This synthetically useful chemistry exploited an intermediacy of unsymmetrical silyloxyallyl cations, which were directly captured by silyl enolates to create the targeted α,α carbon-carbon linkages in a regioselect...

A series of symmetrical and unsymmetrical N,N'-disubstituted aminotroponimines (ATIHs) have been prepared. Substituents ranging from linear to cyclic alkyl groups, chelating ethers, and aryl groups were employed. The corresponding aminotroponiminate zinc complexes were then synthesized and characterized by a number of techniques, including by X-ray crystallography. Herein we report on the inves...

Substituted homoallylic alcohols have been synthesised both by [2,3]-Wittig rearrangement of unsymmetrical bis-allylic ethers and reaction of alkenyl chloromethyl oxiranes with Mg/THF. These substrates were then oxidized using four different oxidants. When the substituted homoallylic alcohols were oxidized with pyridinium chlorochromate or zinc chlorochromate nonahydrate the corresponding carbo...

A comparative study on the catalytic activity of a series of Cp*Ir(NHC)Cl2 complexes in several C-O and C-N coupling processes implying hydrogen-borrowing mechanisms has been performed. The compound Cp*Ir(I)Cl2 (I = 1,3-di-n-butylimidazolylidene) showed to be highly effective in the cross coupling reactions of amines and alcohols, providing high yields in the production of unsymmetrical ethers ...

Allylic and benzylic alcohols are converted into corresponding unsymmetrical ethers when reacted with various orthoesters in the presence of montmorillonite KSF at ambient temperature. A detailed study has been undertaken to examine the mechanism and generality of these reactions with regard to various acidic catalysts, which reveal interesting competitive reactions mainly O-acetylation, togeth...

Polybrominated diphenyl ethers (PBDEs) have been intensively used as flame retardants (FRs) and have become ubiquitous environmental pollutants. PBDEs form hydroxylated PBDEs (OH-PBDEs) as metabolites. Further, some OH-PBDEs and methoxy-PBDEs (MeO-PBDEs) are natural products. These are all compounds of environmental and health concern and it is therefore important to confirm their identity and ...

The equations of unsymmetrical 2-phase induction motors are established and a computer representation is developed from these equations. Computer representation of single phase motors are developed by extension and modification of the unsymmetrical 2-phase induction motors representation. These equations of an unsymmetrical 2-phase induction motors are describe the dynamic performance of equati...

The synthesis and characterization of new meso-substituted and -substituted unsymmetrical metallorphyrins has been described. A new modified Alder method was used for the synthesis of unsymmetrical porphyrins. Reaction of these unsymmetrical porphyrins with metal chlorides and nitrates afforded the corresponding metalloporphyrins in high yields with excellent purity. These porphyrins and their...