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1.
The mass spectra of several 3-methyl-5-(o-R-styryl)-4-nitroisoxazoles have been studied. The fragmentation patterns and mechanisms postulated have been confirmed by the determination of the metastable peaks. 相似文献
2.
FabioMarchetti Claudio Pettinari Augusto Cingolani Lauro Brocanelli Miriam Rossi Francesco Caruso 《Journal of organometallic chemistry》1999,580(2):98
The synthesis of three 1-(4-trifluoromethylphenyl)-3-methyl-4-R1(C=O)-5-pyrazolone proligands LH (L1H; R1=C6H5: L2H; R1=CH3: L3H; R1=CF3) and their interaction with R3Sn(IV) acceptors (R=Me, Bun, Ph) are reported. When R=Me or Bun, aquo (4-acylpyrazolonate)SnR3(H2O) derivatives are obtained and the anionic donors 4-acylpyrazolonate (L−) act in the O–monodentate form. These triorganotin complexes are not stable in chlorohydrocarbon solvents and decompose to R4Sn and bis(4-acyl-5-pyrazolonate)2SnR2. When R=Ph, stable (4-acyl-5-pyrazolonate)SnPh3 derivatives, both in solution and in the solid state, are obtained. The crystal structure of (1-(4-trifluoromethylphenyl)-3-methyl-4-acetylpyrazolon-5-ato)triphenyltin(IV) shows a five-coordinate tin atom in a strongly distorted cis-bipyramidal trigonal environment (axial angle=161.2(2)°) with the acylpyrazolonate donor acting as an asymmetric O2–bidentate species (Sn–O(1)=2.081(6) Å: Sn–O(2)=2.424(5) Å). Electronic effects are responsible for the different behavior shown by these trialkyl and triphenyl derivatives. 相似文献
3.
A. A. Zaitsev D. V. Zaiko I. L. Dalinger V. V. Kachala T. K. Shkineva S. A. Shevelev 《Russian Chemical Bulletin》2009,58(10):2122-2128
A new one-step method for the synthesis of 4-methyl-3(5)-nitropyrazole by nitration of 4-methylpyrazole is developed. Arylation
of 4-methyl-3(5)-nitropyrazole with 1,3,5-trinitrobenzene gives 1-(3,5-dinitrophenyl)-4-methyl-3-nitropyrazole, nitration
of which leads to 1-(3,5-dinitrophenyl)-4-methyl-3,5-dinitropyrazole. The action of 1 equiv. of an O- or S-nucleophile (phenolate,
p-chlorobenzenethiolate and ethoxide ions; anions of glycolanilide and thioglycolanilide) on 1-(3,5-dinitrophenyl)-4-methyl-3,5-dinitropyrazole
led to the substitution of the 5-NO2 group of the pyrazole ring; under the action of one more equivalent of a nucleophile the NO2 group of the benzene ring was substituted. The substitution product of the anion of thioglycolanilide for the 5-NO2 group undergoes the intramolecular cyclization — oxidative nucleophilic hydrogen substitution in the benzene ring under the
action of K2CO3. 相似文献
4.
5.
《Journal of organometallic chemistry》1987,334(3):307-322
The synthesis of a series of tetraorganotin(IV) compounds containing selectively the 2-thienyl, 3-thienyl, 5-methyl-2-thienyl, 5-t-butyl-2-thienyl, 4-methyl-2-thienyl and 3-(2-pyridyl)-2-thienyl groups [L], of formula R4-nSn[L]n (R = Ph, p-tolyl, Me, cyclopentyl, cyclohexyl; n = 1–4) is reported. Features of structural interest deduced from 119mSn Mössbauer and NMR (13C and 119Sn modes) spectra are considered. 相似文献
6.
The complex formation of iron(III) with the trisodium salt of 5-[α-(3-carboxy-5-methyl-4-oxo-2,5-cyclohexadien-1-ylidene)-2-sulfobenzyl]-3-methylsalicylic acid (eriochrome cyanine R) was studied by spectrophotometry. The pure tetrabasic acid of the ligand (H4ER) was prepared and used in the investigation. In the pH range 2.7–4.2 three complexes were detected: a ring-formed dimer Fe2(ER)2, Fe2(ER) and Fe(ER) ; the absolute stability constants (at an ionic strength of 0.1 M and at room temperature (20 ± 3°)) were log k = 37.9, log k = 22.5 and log k = 17.9, respectively. 相似文献
7.
Richard Neidlein Günter Schrder Claus Krieger Danijel Kikelj 《Helvetica chimica acta》1992,75(4):1039-1051
Heterocycles Starting from Bis(alkoxycarbonyl)ketene Ethylene Acetals ( = Dialkyl 2-(1,3-Dioxolan-2-ylidene)propane-1,3-dioate). Synthesis and Properties of a New Class of Pyrazolium Betaines The readily available bis(alkoxycarbonyl)ketene ethylene acetals 1 react with bifunctional nucleophiles to give heterocycles 2–5 (Scheme 1). Their reactions with N,N-dialkylhydrazines lead to the pyrazolium betaines 7a–f (Scheme 4). Cyclic N,N-dialkylhydrazines give spiro compounds 7d–f . The reaction of thioketene acetal 12 and of the derivative 15 of methanetricarboxylic acid with N,N-dimethylhydrazine results in the formation of 3-(methylthio)- and 3-methoxypyrazolium betaine 7g and 7h , respectively (Scheme 4). The chemical reactivity of the synthesized pyrazolium betaines 7 was tested. The structure of the 3-(methylthio) derivative 7g was determined by X-ray analysis. 相似文献
8.
The cloud point extraction behavior of iron(III) and vanadium(V) using 8-quinolinol derivatives (HA) such as 8-quinolinol (HQ), 2-methyl-8-quinolinol (HMQ), 5-butyloxymethyl-8-quinolinol (HO4Q), 5-hexyloxymethyl-8-quinolinol (HO6Q), and 2-methyl-5-octyloxymethyl-8-quinolinol (HMO8Q) and Triton X-100 solution was investigated. Iron(III) was extracted with HA and 4% (v/v) Triton X-100 in the pH range of 1.70-5.44. Above pH 4.0, more than 95% of iron(III) was extracted with HQ, HMQ, and HMO8Q. Vanadium(V) was also extracted with HA and 4% (v/v) Triton X-100 in the pH range of 2.07-5.00, and the extractability increased in the following order of HMQ < HQ < HO4Q < HO6Q. The cloud point extraction was applied to the determination of iron(III) in the riverine water reference by a graphite furnace atomic absorption spectroscopy. When 1.25 × 10−3 M HMQ and 1% (v/v) Triton X-100 were used, the found values showed a good agreement with the certified ones within the 2% of the R.S.D. Moreover, the effect of an alkyl group on the solubility of 5-alkyloxymethyl-8-quinolinol and 2-methyl-5-alkyloxymethyl-8-quinolinol in 4% (v/v) Triton X-100 at 25 °C was also investigated. 相似文献
9.
R-(+)-pulegone (1) is transformed to (R)-5-methyl-2-(phenylsulfinyl)cyclohexanone (5) (65%, 3 steps). Sulfoxide 5 is converted to R-(-)-3,5-dimethylcyclohex-2-en-1-one (4) (53%, 4 steps) and S-(+)-4 (26%, 3 steps). 相似文献
10.
Yu. N. Pozhidaev O. V. Lebedeva S. S. Bochkareva N. S. Shaglaeva L. V. Morozova M. G. Voronkov 《Russian Journal of Applied Chemistry》2008,81(10):1837-1841
Formation of nanocomposites in the sol-gel systems RSiX3 [R = CH3 (I), C6H5 (II), X = Cl; R = ClCH2 (III), X = OC2H5]-polyvinylazole [(-CH2-C(Y)H-) n , Y = pyrazolyl, imidazolyl, 4-pyridinyl, 2-methyl-5-pyridinyl], and also I-1-vinyl-4,5,6,7,-tetrahydroindole using was studied. The composition and structure of the resulting nanocomposites were analyzed. 相似文献
11.
Nitration of 4-methyl-2-[2-(nitro-2-furyl)vinyl]thiazole with a mixture of concentrated nitric and sulfuric acids leads to 4-methyl-5-nitro-2-[2-(3,5-dinitro-2-furyl)vinyl]thiazole. Under the same conditions 2-methyl- and 2-acetamido-4-[1-R-2-(5-nitro-2-furyl)vinyl]thiazoles (R=CH3, Cl) are nitrated in the 3 position of the furan ring, 2-amino-4-[1-chloro-2-(5-nitro-2-furyl)vinyl]thiazole is nitrated in the 5 position of the thiazole ring and 2-acetamido-5-nitro-4-[2-(2-furyl)vinyl]thiazole undergoes profound changes. Under the influence of a mixture of of nitric acid and acetic anhydride the latter compound is converted quantitatively to the 5-nitro derivative (with respect to the furan ring), whereas 4-[2-(5-nitro-2-furyl)vinyl]thiazole derivatives do not undergo reaction.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 314–317, March, 1977. 相似文献
12.
Zusammenfassung 5-Chlor-2-(N-methyl-jodmethansulfonamido)-benzophenon (6 b) reagiert mit flüss. NH3 zu 6-Chlor-4-hydroxy-1-methyl-4-phenyl-3,4-dihydro-1H-2,1-benzothiazin-2,2-dioxid (7), mit NH3 in absol. Alkohol zu 6-Chlor-4-hydroxy-3-jod-1-methyl-4-phenyl-3,4-dihydro-1H-2,1-benzothiazin-2,2-dioxid (9). Der Mechanismus dieser Reaktionen wird diskutiert.
The reaction of ammonia with 5-Chloro-2-(N-methyl-iodo-methanesulfonamido)-benzophenone
The reaction of 5-chloro-2-(N-methyl-jodomethanesulfon-amido)-benzophenone (6b) with liquid or absol. alcoholic ammonia leads to 6-chloro-4-hydroxy-1-methyl-4-phenyl-3,4-dihydro-1H-2,1-benzothiazine-2,2-dioxid (7) and 6-chloro-4-hydroxy-3-jodo-1-methyl-4-phenyl-3,4-dihydro-1H-2,1-benzothiazine-2,2-dioxid (9) resp. The mechanism of these reactions is discussed.相似文献
13.
Raúl Ramírez-Trejo Angelina Flores-Parra José Adrián Peña-Hueso Edgar Mijangos Rosalinda Contreras Norah Barba-Behrens 《Polyhedron》2010
Herein we report the syntheses and structural analyses of three coordination compounds Co(L)2 (3), Ni(L)2, (4) and Cu(L)2 (5) (L = bis[(4R,5R)-4-methyl-5-phenyl-4,5-dihydro-thiazol-2-yl]-amine) prepared by template reactions from the optically active ligand (4R,5R)-4-methyl-5-phenyl-4,5-dihydro-thiazol-2-yl-amine (1) and CoCl2·6H2O, NiBr2·3H2O or Cu(OAc)2·H2O The template reactions involve the condensation of two molecules of thiazol-2-yl-amine and elimination of one NH3. The resulting bidentate ligand coordinates to the metal ion through the imine nitrogen atoms forming a six-membered ring, presenting an electronic delocalization which averages the four M–N bond lengths. The distorted tetrahedral geometry of the metal atoms gives place to complex electronic spectra for compounds 3–5. A mixed ionic compound (6) formed by three cations (4S,5S)-3,4-dimethyl-5-phenyl-thiazolidin-2-ylidene ammonium, one dianion tris-(thiocyano)bromide cobaltate and one bromide, obtained from reaction of (4S,5S)-3,4-dimethyl-5-phenyl-thiazolidin-2-ylidene ammonium thiocyanate (2) and CoBr2 is also described. Compounds 3–6 were characterized in the solid state by UV–Vis–NIR and IR spectroscopy, mass spectrometry and X-ray diffraction analyses. Metal···H–C, S···H–C interactions were observed in 3–6, whereas in 6, also Br···H–N, Br···H–C and Br···S, S···S short contacts were found. 相似文献
14.
《Tetrahedron letters》1986,27(33):3881-3884
The optically active (2R, 3R)-3-[(3R)-(E)-Benzyloxymethoxy-5-methyl-1-hexenyl]-2-(3-butenyl)-2-methyl-1-cyclopentanone (8) was synthesized as a precursor of vitamin D3(5) by palladium-catalyzed syn-SN2′ cyclization of [Z,Z(22S, 23R)]-ene oxide 6 as a key reaction. 相似文献
15.
4-Methyl- and 4-benzyl-5-aminoisoquinolin-1-ones are close analogues of the water-soluble PARP-1 inhibitor 5-AIQ. Their synthesis was approached through Pd-catalysed cyclisations of N-(2-alkenyl)-2-iodo-3-nitrobenzamides. Reaction of N,N-diallyl-2-iodo-3-nitrobenzamide with Pd(PPh3)4 gave a mixture of 2-allyl-4-methyl-5-nitroisoquinolin-1-one and 2-allyl-4-methylene-5-nitro-3,4-dihydroisoquinolin-1-one. N-Benzhydryl-N-cinnamyl-2-iodo-3-nitrobenzamide similarly gave 2-benzhydryl-4-benzyl-5-nitroisoquinolin-1-one and 2-benzhydryl-4-benzylidene-5-nitro-3,4-dihydroisoquinolin-1-one. The isomeric products are not interconvertible. A deuterium-labelling study indicated that the isomers were formed by different pathways: a π-allyl-Pd route and the classical Heck route. The corresponding secondary amides N-allyl-2-iodo-3-nitrobenzamide and N-((substituted)-cinnamyl)-2-iodo-3-nitrobenzamide gave good yields of the required 4-methyl- and 4-((substituted)-benzyl)-5-nitroisoquinolin-1-ones, respectively, under optimised conditions (Pd(PPh3)4, Et3N, Bu4NCl, 150 °C, rapid heating). Hydrogenation of the nitro groups gave 4-methyl- and 4-benzyl-5-aminoisoquinolin-1-ones, which were potent inhibitors of PARP-1 activity. 相似文献
16.
Cyclization reactions with 2-(β-styryl)benzylamines 5-Phenyl-1H-2-benzazepines Cyclization of the urea derivative 3 with POCl3 to give 2-(4-methyl-1-piperazinyl)-4-phenylquinoline ( 4 ) was carried out in analogy to the quinoline synthesis of Foulds & Robinson. This reaction was used for the preparation of 2-benzazepines. The trisubstituted ureas 6 and 8 , derived from the 2-(β-styryl)-benzylamines 5 , were cyclized with POCl3 to yield the 3-amino-5-phenyl-1H-2-benzazepines 7 and 9 , respectively. Similarly, cyclization of the corresponding acetyl-derivatives 10 gave the 3-methyl-5-phenyl-1H-2-benzazepines 12 . On the other hand, the disubstituted urea 15 , cyclized under the same conditions to the 1-methyl-1-phenylisoindoline derivative 16 , and 2-(β-styryl)benzylamine ( 5a ) on treatment with phosgene gave the isoindoline 17 in an analogous manner. 相似文献
17.
The hydrogenation of 2′, 3′-O-isopropylidene-5-methyluridine (1) in water over 5% Rh/Al2O3 gave (5 R)- and (5 S)-5-methyl-5, 6-dihydrouridine (2) , separated as 5′-O-(p-tolylsulfonyl)- (3) and 5′-O-benzoyl- (5) derivatives by preparative TLC. on silica gel and ether/hexane developments. The diastereoisomeric differentiation at the C(5) chiral centre depends upon the reaction media and the nature of the protecting group attached to the ribosyl moiety. The synthesis of iodo derivatives (5 R)- and (5 S)- 4 is also described. The diastereoisomers 4 were converted into (5 R)- and (5 S)-2′, 3′,-O-isopropylidene-5-methyl-2, 5′-anhydro-5, 6-dihydrouridine (7) . 相似文献
18.
Yu. O. Remizov L. M. Pevzner M. L. Petrov 《Russian Journal of General Chemistry》2018,88(7):1402-1410
By arylation of 2-methyl-3-acetylfuran via the Gomberg–Bachmann reaction 5-(4-ethoxycarbonylphenyl)-, 5-(2-nitrophenyl), and 5-(4-nitrophenyl)-2-methyl-3-acetylfurans were synthesized. Carboethoxyhydrazones of 2-methyl-5-phenyl-3-acetylfuran and its phenyl-substituted analogs when treated with thionyl chloride form 4-(5-aryl-2-methylfuran-3-yl)-1,2,3-thiadiazoles by the Hurd–Mori reaction. Thermal stability of obtained compounds increases with the increase in electron-acceptor action of substituent in phenyl ring. Opening of thidiazole ring in the compounds synthesized under the action of potassium tert-butylate in THF in the presence of alkyl iodides leads to the corresponding alkylthioethynylfurans. Performing the reaction with potassium carbonate in DMF in the presence of excess morpholine permits the preparation of (2-methyl-5- arylfuran-3-yl)thioacetylmorpholides. 相似文献
19.
James Elver Johnson Richard Hodzi Susan L. Todd Patrice De Meester Shirley S. C. Chu 《Journal of heterocyclic chemistry》1986,23(5):1423-1426
Alkylation of potassium p-nitrobenzohydroxamate with 1,4-dibromobutane gave 2-(p-nitrobenzoyl)tetrahydro-2H-1,2-oxazine (3). The X-ray crystal structure of 3 has been determined. The crystals are monoclinic, space group P21/n with a = 6.749(1), b = 7.644(1), c = 21.557(2)Å, β = 98.89(1), V = 1098.8(2)Å3 and Z = 4. The structure, which was refined to R = 0.039 using 1340 observed reflections, shows the oxazine and carbonyl oxygen atoms trans to each other. Alkylation of potassium benzohydroxamate with 1,3-dibromobutane gave a mixture of 3-methyl-2-benzoyloxazolidine (4) and 5-methyl-2-benzoyloxazolidine (5). The 1H and 13C nmr spectra of the mixture of 4 and 5 indicates that these cyclic hydroxamates exist predominantly in the s-trans conformation. 相似文献
20.
Matsuo Nonoyama 《Transition Metal Chemistry》1980,5(1):269-271
Summary [(R)-2-Methyl-1,4,7-triazacyclononane][1,1,1-tris(aminomethyl)ethane]cobalt(III) has been prepared and separated into two isomers which show weak Cotton effects in the1A11T1 region (d-electron transition) compared with that of bis[(R)-2-methyl-1,4,7-triazacyclononane]cobalt(III). The effect is comparable to that of tetraammine[(R)-1,2-diamino propane]cobalt(III). The circular dichroism spectra of the mono complex change markedly upon addition of sodium sulphate. The chelate rings are more flexible in the mono than in the bis complex. Some other related mono[(R)-2-methyl 1,4,7-triazacyclononane]cobalt(III) and [(R)-2-methyl-1,4,7 triazacyclononane][1,1,1-tris(aminomethyl)ethaneI nickel (II) complexes have also been prepared and characterized. 相似文献