Formation and structure of 1-Amino-4-methyl-4-(4-methyl-5-phenyl-1H-pyrazol-3-ylamino)-3-phenyl-4,5-dihydro-1H-pyrazol-5-one

The title compound 3 was obtained during the rearrangement of isoxazol-5-yl hydrazine 1 to 1-aminopyrazolone 2 at 115°. X-ray analysis of the corresponding benzylidene derivative allowed us to achieve the structure assignment.     

Crystal structure-reactivity correlation in single-crystalline photochromism of 1,2-bis(2-methyl-5-phenyl-3-thienyl)perfluorocyclopentene

Single-crystalline photochromism of 1,2-bis(2-methyl-5-phenyl-3-thienyl)perfluorocyclopentene 1a was followed in situ by X-ray crystallographic analysis. The crystal of 1a has two molecules with different conformations in the crystallographic asymmetric unit. The X-ray analysis of the photoirradiated crystal showed that the photocyclization reaction of the molecule with the shorter distance between the reactive carbons prevails over the reaction of the other molecule. The mechanism has been discussed based on the calculation of the electronic transitions of the two molecules in the different conformations. The photocyclization quantum yield was determined to be 1 (100%) in the crystal.     

Synthesis,Molecular Structure,and Spectral Characteristics of Lead(II) Complexes with 1,5-Dimethyl-4-[2-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)hydrazinyl]-2-phenyl-1,2-dihydro-3H-pyrazol-3-one

Russian Journal of General Chemistry - Pb(II) cations form complexes with...     

Synthesis and Crystal Structure of Trans-4-[(5-(2,4-Dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one

The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl-1-phenyl-1H-pyra-zol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1 with a = 8.9438(4), b = 11.6065(5), c = 14.2215(6) , α = 112.566(1), β = 92.324(2), γ = 102.91(1)o, V = 1315.65(10) 3, Z = 2, Dc = 1.344 g/cm3, μ(MoKα) = 0.282 mm-1, λ = 0.71073 , F(000) = 552, the final R = 0.0587 and wR = 0.1578 for 5071 observed reflections (I > 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable trans isomer. Intra-and intermolecular C(12)-H(12)···O(1) and C(28)-H(28)···O(1)#1 hydrogen bonds were observed in the title compound.     

Preparation of 3(5)-phenyl-1-hydroxypyrazole 2-oxide and 4-methyl-3(5)-phenyl-1-hydroxypyrazole 2-oxide

Nitrosation of acrylophenone oxime or of methacrylophenone oxime with n-butyl nitrite in the presence of pyridine and copper(II) sulfate gives the copper complexes of the title compounds. The free 1-hydroxypyrazole 2 -oxides are isolated by treating the copper complexes with dilute sodium hydroxide, filtration, and acidification of the basic filtrates. The title compounds are the first examples of 1-hydroxypyrazole 2 -oxides in which the C3(5) ring position is unsubstituted.     

4-取代苯次甲亚胺-5-(1-苯基-3-甲基-5-氯吡唑)-2H-1,2,4-三唑-3-硫酮的合成

以乙醇为溶剂,冰醋酸为催化剂,4-氨基-5-(1-苯基-3-甲基-5-氯吡唑)-1,2,4-三唑-3-硫酮(1)与芳醛经缩合反应合成了7个新型的4-取代苯次甲亚胺-5-(1-苯基-3-甲基-5-氯吡唑)-4H-1,2,4-三唑-3-硫酮(3a~3g),收率66%~74%,其结构经1H NMR,IR及元素分析表征。合成4-(苯次甲亚胺)-5-(1-苯基-3-甲基-5-氯吡唑)-2H-1,2,4-三唑-3-硫酮(3a)的最佳反应条件为:以乙醇为溶剂,乙酸为催化剂,1 10 mmol,n(苯甲醛)∶n(1)=1.2,于75℃反应3 h,产率74%。     

Thermal decomposition product of 1,2-bis(2-methyl-1-benzofuran-3-yl)perfluorocyclopentene

1,2-Bis(2-methyl-1-benzofuran-3-yl)perfluorocyclopentene shows photochromism in n-hexane at room temperature. We have identified a new compound produced by the thermal decomposition in a mixture of cis- and trans-decahydronaphthalene above 100?°C in the absence of light.     

Hydroborierung von 3-methyl-1,3-butadien mit 1,2:1,2-bis(tetramethylen)diboran(6)

The nature of the hydroboration product obtained from 3-methyl-1,3-butadiene and 1,2 : 1,2-bis(tetramethylene)diborane(6) (1) allows for the discussion of the reaction mechanism. The hydroboration proceedsby retention of the cyclic structure in the first step, followed by exchange of BH and BC bonds and final cyclic hydroboration to give 1-(boracyclopentyl)-4-(3-methylboracyclopentyl)butane (5). The structural assignment of 5 is based on ¹H, ¹¹B and ¹³C NMR data.     

Synthesis of 1,2-bis[2-methyl-5(3,4-difluorophenyl)-3-thienyl] perfluorocyclopentene

2-Methylthiophene (1) was treated at 0°C with liquid bromine to form 3,5-dibromo-2-methylthiophene (2) which reacted with tributyl borate to give 2-methyl-3-bromo-5-boronate thiophene (3) at −78°C. Treatment of 3 with 3,4-difluorobrombenzene gave 2-methyl-3-bromo-5-(3,4-difluorophenyl)thiophene (4). Finally, a novel photochromic dithienylethene compound, 1,2-bis [2-methyl-5(3,4-difluorophenyl)-3-thienyl]perfluorocyclopentene (DT-1), was synthesized by the reaction of 4 with perfluorocyclopentene at −78°C. The compound (DT-1) was characterized by IR, NMR, MS, elemental analysis and its photochromic behavior was also discussed. __________ Translated from Chinese Journal of Organic Chemistry, 2007, 27(10): 1282–1284 [译自: 有机化学]     

Oxidative ring-opening of rel-(2R,3R,5S)-5-aryl-2-benzoylamino-6,7-bis(methoxycarbonyl)-2,3-dihydro-1-oxo-3-phenyl-1H,5H-pyrazolo[1,2-a]-pyrazoles. Synthesis of rel-(2R,3R)-3-phenyl-3-[5-aryl-3,4-bis(methoxycarbonyl)pyrazolyl-1]alanine esters

rel-(2R,3R)-N-Benzoylamino-6,7-bis(methoxycarbonyl)-2,3-dihydro-1-oxo-1H,5H-pyrazolot[1,2-a]-pyrazoles 5 , accesible by cycloaddition of dimethyl acetylenedicarboxylate ( 3 ) to (1Z)-rel-(4R,5R)-1-aryl-methylidene-4-benzoylamino-5-phenyl-3-pyrazolidinone-1-azomethine imines 4 , undergo oxidative ring cleavage with methanolic bromine giving rel-(2R,3R)-N-benzoyl-3-phenyl-3-[5-aryl-3,4-bis(methoxy-carbonyl)pyrazolyl-1]alanine methyl esters 6 as products.     

原位生成的Ph3C+均相有机催化剂催化4,4’-芳亚甲基-二（3-甲基-1-苯基-1H-吡唑-5-醇）高效合成（英文）简

Trityl chloride (Ph₃CCl) efficiently catalyzes the condensation of 3-methyl-1-phenyl-1H-pyrazol- 5(4H)-one and aromatic aldehydes under mild and solvent-free conditions, affording 4,4''- (arylmethylene)-bis(3-methyl-1-phenyl-1H- pyrazol-5-ol)s in high to excellent yields and in short reaction time. The presence of the requisite organocatalytic trityl carbocation (Ph₃C⁺) species was confirmed by analysis of infrared, ¹H NMR, and ultra violet spectral data. A plausible mechanism was proposed for the reaction based on the observations and literature precedent.     

Synthesis and Antimicrobial Activity of Diethyl [(Substituted Phenyl)(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyl]phosphonates

Russian Journal of General Chemistry - A series of structurally diverse and biologically potent diethyl [(substituted phenyl)(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyl]phosphonates has...     

Transformations of 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one under various conditions of cyclopropyldiazonium generation

Cyclopropyldiazonium generated by basic decomposition of N-cyclopropyl-N-nitrosourea easily entered into an azo coupling reaction with 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one (2) to give the corresponding cyclopropylhydrazone in up to 90% yield. Competitive processes occurring under the conditions of cyclopropyldiazonium generation by nitrosation of cyclopropylamine with butyl nitrite mainly include nitrosation of the starting pyrazolone 2. Subsequent transformations of the resulting heterocyclic 3-methyl-1-phenyl-1H-pyrazole-4,5-dione 4-oxime yield 4-[cyclopropyl(oxido)imino]-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2151–2155, December, 2006.     

Palladium(II) complexes of Schiff bases derived from 5-amino-2,4-(1H, 3H)pyrimidinedione (5-aminouracil) and 1,2-dihydro-1,5-dimethyl-2-phenyl-4-amino-3H-pyrazol-3-one

Summary New palladium(II) complexes of Schiff bases, obtained from 5-aminouracil, (AUH), and acetylacetone (AUAcAcH₂), benzaldehyde (AUBALH), furan-2-aldehyde (AUFALH), 2-hydroxynaphthaldehyde (AUNALH₂), pyridine-2-aldehyde (AUPyALH) or salicylaldehyde (AUSALH₂) and from 1,2-dihydro-1,5-dimethyl-2-phenyl-4-amino-3H-pyrazol-3-one (AAPy) and acetylacetone (AAPyAcAcH), 2-hydroxyacetophenone (AAPyAPH), furan-2-aldehyde (AAPyFAL), pytidine-2-aldehyde (AAPyPyAL), or salicylaldehyde (AAPySALH), have been prepared. The complexes, with formulae PdL₂Cl₂ (L=AUBALH, AUFALH or AUSALH₂); PdLCl₂ (L=AUAcAcH₂, AUNALH₂, AUPyALH, AAPyFAL or AAPyPyAL) and PdLCl (L=AAPyAcAc or AAPySAL) were characterized by elemental analysis, i.r. and electronic spectral studies, thermogravimetric analyses and magnetic and conductance measurements. The x-ray powder diffraction pattern of one of the complexes was also examined. The complexes were screened for their possible antitumour activityin vitro.