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Preparation of Pyrazole–Pyrazolate Half‐Sandwich Complexes of Ruthenium and Osmium
European Journal of Inorganic Chemistry, 2010AbstractPyrazole (HRpz) [MCl(η6‐p‐cymene)(HRpz)L]BPh4 (1–8) and imidazole (HIm) complexes [MCl(η6‐p‐cymene)(HIm)L]BPh4 (9–10) [M = Ru, Os; R = H, 3‐Me, 3,5‐Me2; L = P(OEt)3, PPh(OEt)2, PPh2OEt, CNtBu] were prepared by allowing the dichloro compounds MCl2(η6‐p‐cymene)L to react with the appropriate azole in the presence of NaBPh4.
ALBERTIN, Gabriele +3 more
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Pyrazoles VI: The electron‐releasing capacity of the pyrazole ring
Journal of Heterocyclic Chemistry, 1969AbstractUV and PMR spectral data and CO frequencies of some methylpyrazoles containing in the 3‐, 4‐ or 5‐position, a formyl‐, acetyl‐ or ethoxycarbonyl group are reported. These data confirm earlier conclusions that, in particular, the 4‐pyrazolyl group acts as an electron releasing group.
C. Wijnberger, Clarisse L. Habraken
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Organometallics, 2000
Compounds containing bridging pyrazolate and terminal pyrazolate or pyrazole ligands of type Ni2(PMe3)2(L-κN)(μ2-η1:η3-CH2-o-C6H4)(μ2-L-κN,N‘) (L = 3,5-dimethylpyrazolate (Pz‘ ‘), 3b, or 3,5-di-tert-butylpyrazolate (Pz**), 3c); Ni2(PMe3)2(Pz**-κN)(μ2-η1:η3-CH2-o-C6H4)(μ2-Pz‘ ‘-κN,N‘), 4, and [Ni2(PMe3)2(HPz‘ ‘-κN)(μ2-η1:η3-CH2-o-C6H4)(μ2-Pz-κNN‘)](X ...
Jorge A. López +5 more
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Compounds containing bridging pyrazolate and terminal pyrazolate or pyrazole ligands of type Ni2(PMe3)2(L-κN)(μ2-η1:η3-CH2-o-C6H4)(μ2-L-κN,N‘) (L = 3,5-dimethylpyrazolate (Pz‘ ‘), 3b, or 3,5-di-tert-butylpyrazolate (Pz**), 3c); Ni2(PMe3)2(Pz**-κN)(μ2-η1:η3-CH2-o-C6H4)(μ2-Pz‘ ‘-κN,N‘), 4, and [Ni2(PMe3)2(HPz‘ ‘-κN)(μ2-η1:η3-CH2-o-C6H4)(μ2-Pz-κNN‘)](X ...
Jorge A. López +5 more
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2008
Five-membered ring systems containing two nitrogen atoms adjacent to each other are called pyrazoles. This chapter serves to cover the extensive literature on pyrazoles during the 10 year period, 1996–2006. The previous two chapters of this series, on pyrazoles, dealt more with the theoretical, experimental structural, and thermodynamic methods and ...
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Five-membered ring systems containing two nitrogen atoms adjacent to each other are called pyrazoles. This chapter serves to cover the extensive literature on pyrazoles during the 10 year period, 1996–2006. The previous two chapters of this series, on pyrazoles, dealt more with the theoretical, experimental structural, and thermodynamic methods and ...
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1983
Publisher Summary Pyrazoles occur in two nonaromatic forms (the 3H- and 4H-pyrazoles). This chapter focuses on 4H-pyrazoles, which are cyclic azines. The most used method for the synthesis of 4H-pyrazoles employs 2,2-disubstituted 1,3-diketones and hydrazine.
Michael P. Sammes, Alan R. Katritzky
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Publisher Summary Pyrazoles occur in two nonaromatic forms (the 3H- and 4H-pyrazoles). This chapter focuses on 4H-pyrazoles, which are cyclic azines. The most used method for the synthesis of 4H-pyrazoles employs 2,2-disubstituted 1,3-diketones and hydrazine.
Michael P. Sammes, Alan R. Katritzky
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Inorganic Chemistry, 2007
Compound cis,fac-[Mo(eta3-allyl)(CO)2(Hdmpz)3]BAr'4 (1) (Hdmpz = 3,5-dimethylpyrazole, Ar' = 3,5-bis(trifluoromethyl)phenyl) undergoes rapid substitution of one of the pyrazole ligands by anions, including the low nucleophilic ReO4-, a reaction that afforded [Mo(OReO3)(eta3-allyl)(CO)2(Hdmpz)2] (2), structurally characterized by X-ray diffraction.
Daniel Miguel +6 more
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Compound cis,fac-[Mo(eta3-allyl)(CO)2(Hdmpz)3]BAr'4 (1) (Hdmpz = 3,5-dimethylpyrazole, Ar' = 3,5-bis(trifluoromethyl)phenyl) undergoes rapid substitution of one of the pyrazole ligands by anions, including the low nucleophilic ReO4-, a reaction that afforded [Mo(OReO3)(eta3-allyl)(CO)2(Hdmpz)2] (2), structurally characterized by X-ray diffraction.
Daniel Miguel +6 more
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Octahedral molybdenum iodide clusters with pyrazole or pyrazolate ligands
Dalton TransactionsHexaaqua or hexahydroxo molybdenum iodide cluster complexes obtained in one step were shown to be accessible complexes for synthesis of clusters with pyrazole or pyrazolate ligands.
Ksenia S. Kozlova +4 more
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The Synthesis of Phosphonyl Pyrazoles
Phosphorus, Sulfur, and Silicon and the Related Elements, 1999Phosphonyl hydrazones react with DMF/POCl3 to afford 3-phos-phonyl pyrazoles.Phosphonyl methylene hydrazones react with DMF/POCl3 to provide 4-phosphonyl pyrazoles. 5-phosphonyl pyrazoles are obtained from the reaction of phosphonyl chlorovinylaldchydes with phenylhydrazine.
Guo-Xiang Xu +7 more
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1983
Publisher Summary This chapter discusses the 3 H -pyrazoles that have been isolated or characterized spectroscopically. 3 H -Pyrazoles can be synthesized from (1) diazo compounds and alkynes, (2) diazo compounds and alkenes bearing suitable leaving groups, (3) diazo compounds by other intermolecular processes, (4) cyclization of vinyl diazo compounds,
Alan R. Katritzky, Michael P. Sammes
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Publisher Summary This chapter discusses the 3 H -pyrazoles that have been isolated or characterized spectroscopically. 3 H -Pyrazoles can be synthesized from (1) diazo compounds and alkynes, (2) diazo compounds and alkenes bearing suitable leaving groups, (3) diazo compounds by other intermolecular processes, (4) cyclization of vinyl diazo compounds,
Alan R. Katritzky, Michael P. Sammes
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2009
Also known as Knorr reaction. Reaction of hydrazine or substituted hydrazine with 1,3-dicarbonyl compounds to provide the pyrazole or pyrazolone ring system. Cf. Paal–Knorr pyrrole synthesis.
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Also known as Knorr reaction. Reaction of hydrazine or substituted hydrazine with 1,3-dicarbonyl compounds to provide the pyrazole or pyrazolone ring system. Cf. Paal–Knorr pyrrole synthesis.
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