The new 3,5-(substituted) pyrazoles and isoxazoles were prepared by reaction of (N'(1)E, N'(3)E)- N'(1), N'(3)-bis (3,4,5-substitutedbenzylidene)malonohydrazide with hydrazine hydrate and hydroxylamine hydrochloride respectively under solvothermal conditions involving an ecofriendly method without any environmental pollution, the yield are in the range of 75-96%. The structure of the new compou...

1,3-Dipolar cycloaddition of the anion of diethyl 1-diazomethylphosphonate, generated in situ from diethyl 1-diazo-2-oxopropylphosphonate (Bestmann-Ohira reagent), with conjugated nitroalkenes provides regioisomerically pure phosphonylpyrazoles in moderate to good yield. These pyrazoles are formed in one pot via spontaneous elimination of the nitro group. However, nitropyrazoles could be synthe...

abstarct:a simple one-pot synthesis of pyrano[ 2,3-c]pyrazoles was developed by a three-component reaction of various benzaldehydes, malononitrile and 1-phenyl or hydro-3-methyl-1h-pyrazol-5(4h)-one in the presence of n-methyl pyridinium p-toluene sulfonate (nmpyts) as a catalyst. all of the synthesized compounds were identified by ir, 1h nmr, 13c nmr and mass spectroscopy techniques. in the me...

Some N-acetyl pyrazoles including 3-(3,4-dichlorophenyl)-5-(substituted phenyl)-4,5-dihydro1 H-pyrazole-1-yl-ethanones have been synthesised by solvent free cyclization cum acetylation of chalcones including substituted styryl 3,4-dichlorophenyl ketones using hydrazine hydrate and acetic anhydride in presence of catalytic amount of fly-ash: H2SO4 catalyst. The yield of these N-acetyl pyrazole d...

A visible-light photoredox functionalization of 3,4-dihydro-quinoxalin-2-ones with pyrazolones using an inexpensive organophotoredox catalyst is described. The reaction uses 9,10-phenanthrenedione as photocatalyst, a very simple and cheap HP single Blue LED (455 nm) source oxygen from air terminal oxidant, obtaining the corresponding acetylated pyrazoles good yields. can be extended to other ni...

Abstract Novel acyl pyrazoles and triazoles have been prepared by means of the oxidative amidation aldehydes in presence requisite azole. Yields range from modest to good both cases, some limitations substrate scope discovered. Acyl were treatment a mixture aldehyde pyrazole with an oxoammonium salt bearing nitrate anion. In case triazoles, functionalization was performed using sodium persulfat...

The Non-Hydrogenative Parahydrogen-Induced Polarization (NH-PHIP) technique, which is referred to as Signal Amplification by Reversible Exchange (SABRE), has been reported to be applicable to various substrates and catalysts. For more detailed studies, pyridine was mainly examined in the past. Here, we examined several pyrazole derivatives towards their amenability to this method using Crabtree...

Conditions allowing the one pot 2,5-diheteroarylation of 2,5-dibromothiophene derivatives in the presence of palladium catalysts are reported. Using KOAc as the base, DMA as the solvent and only 0.5-2 mol % palladium catalysts, the target 2,5-diheteroarylated thiophenes were obtained in moderate to good yields and with a wide variety of heteroarenes such as thiazoles, thiophenes, furans, pyrrol...