1 -Phenyl-3,5-dimethylpyrazole

C32H8oN8U2r Tetrakis(diethylamido)uranium(IV) dimer, 42B, 868 C33H3,ClN408Rh2, (7,16-Dihydro-6,8,15,17-tetramethyldibenzo[b,i]-(1,4,8,11)tetraazacyclotetradecinato)tetracarbonyldirhodium(l) perchlorate toluene solvate, 44B, 949 C33H3sAgN703, Tris(1-phenyl-3,5-dimethylpyrazole)silver(I) nitrate, 45B, 1203... 

Although the thermodynamic aspects of acylotropy are well documented, there have been few kinetic studies of the process. The activation barrier is much higher than for prototropy and only Castells et al. (72CC709) have succeeded in observing a coalescence phenomenon in H NMR spectra. At 215 °C in 1-chloronaphthalene the methyl groups of N-phenyl-3,5-dimethylpyrazole-l-carboxamide coalesce. The mechanism of dissociation-combination explains the reversible evolution of the spectra (Scheme 9). 

Abbreviations acac, acetylacetonate Aik, alkyl AN, acetonitrile bpy, 2,2 -bipyridine Bu, butyl cod, 1,5- or 1,4-cyclooctadiene coe, cyclooctene cot, cyclooctatetraene Cp, cyclopentadienyl Cp, pentamethylcyclopenladienyl Cy, cyclohexyl dme, 1,2-dimethoxyethane dpe, bis(diphenyl-phosphino)ethane dppen, cis-l,2-bis(di[Atenylphosphino)ethylene dppm, bis(diphenylphosphino) methane dppp, l,3-bis(diphenylphosphino)propane eda,ethylenediamine Et,ethyl Hal,halide Hpz, pyrazole HPz, variously substituted pyrazoles Hpz, 3,5-dimethylpyrazole Me, methyl Mes, mesityl nbd, notboma-2,5-diene OBor, (lS)-endo-(-)-bomoxy Ph, phenyl phen, LlO-phenanthroline Pr, f opyl py, pyridine pz, pyrazolate Pz, variously substituted pyrazolates pz, 3,5-dimethylpyrazolate solv, solvent tfb, tetrafluorobenzo(5,6]bicyclo(2.2.2]octa-2,5,7-triene (tetrafluorobenzobanelene) THE, tetrahydrofuran tht, tetrahydrothicphene Tol, tolyl. 

Bis(3,5-dimethylpyrazol-l-yl)cyclotriphosphazene containing phenyl substituents at the phosphorus atoms (R) reacts with molybdenum and tungsten hexacar-bonylstogive34(R = Ph M = Mo, W) [94JCS(D)63]. IfRj = N(Me)(CH2)20, compounds 34 (R2 = N(Me)(CH2)20 M = Mo, W) having better solubility in organic solvents are produced. Their structures show the novel tridentate NNN feature of the ligands. 

Attempts were made to perform heterocyclization with 4-phenylethynyl- and 4-ethynyl-5-aminomethyl-l,3-dimethylpyrazole where, on the one side, a strained six-membered ring can be formed, and, on the other side, the aliphatic amino group is more nucleophilic than the aromatic (Scheme 112). However, all attempts to cyclize the ethynylpyrazole and its phenyl analog failed (86TH1). 

Abbreviations aapy, 2-acetamidopyridine Aik, alkyl AN, acetoniuile Ar, aryl Bu, butyl cod, 1,5-cyclooctadiene COE, cyclooctene COT, cyclooctatetraene Cp, cyclopentadienyl Cp , penta-methylcyclopentadienyl Cy, cyclohexyl DME, 1,2-dimethoxyethane DME, dimethylformamide DMSO, dimethyl sulfoxide dmpe, dimethylphosphinoethane dppe, diphenylphosphinoethane dppm, diphenylphosphinomethane dppp, diphenylphosphinopropane Et, ethyl Ec, feirocenyl ind, inda-zolyl Me, methyl Mes, mesitylene nb, norbomene orbicyclo[2.2.1]heptene nbd, 2,5-norbomadiene OTf, uiflate Ph, phenyl PPN, bis(triphenylphosphoranylidene)ammonium Pi , propyl py, pyridine pz, pyrazolate pz, substituted pyi azolate pz , 3,5-dimethylpyrazolate quin, quinolin-8-olate solv, solvent tfb, teti afluorobenzobaiTelene THE, tetrahydrofuran THT, tetrahydrothiophene tmeda, teti amethylethylenediamine Tol, tolyl Tp, HB(C3H3N2)3 Tp , HB(3,5-Me2C3HN2)3 Tp, substituted hydrotiis(pyrazol-l-yl)borate Ts, tosyl tz, 1,2,4-triazolate Vin, vinyl. 

HPA = (4-pyridylthio)aceticacid 2-fur = 2-furoate a-fur = a-furoate = ([Pg.116]

The crystal structure of tris(l-phenyl-3,5-dimethylpyrazole)silver(I) nitrate (3) has been determined.63 The Ag+ ion sat at the centre of a triangle of 3 Ns from the pyrazole rings and the Ag—N bond lengths were about 224 pm. The nitrate groups were situated between the silver ions in the crystal lattice but the separations were of the order of 550-700 pm—too far... 

Selenium acetylacetone also undergoes the following reactions 1 One molecule of the compound reacts with two molecules of p-nitro-phenylhydrazine to give p-nitrobenzeneazoacetylacetone, 1-p-nitro-phenyl-3 5-dimethylpyrazole and di-p-nitrophenylhydrazinoacetyl-acetone. With one or two molecular proportions of aniline, selenium and 1 3-dianilinoacetylacetone are obtained,... 

In 1896 Knorr and Stolz succeeded in diazotizing 4-amino-1-phenyl-2,3-dimethylpyrazole and so obtained the first diazonium salt with a pyrazole nucleus.26 Much later, Morgan and Reilly diazotized 4-amino-3,5-dimethylpyrazole and studied the reactions of the resultant diazonium salt (49).27,28 In aqueous solution it coupled with /3-naphthol and the crystalline diazonium chloride was quite stable. However, these workers did not isolate the free diazo compound. The diazo compounds can be readily obtained by treating the... 

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