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1.
A. N. Chernega M. Yu. Antipin Yu. T. Struchkov A. V. Ruban V. D. Romanenko 《Journal of Structural Chemistry》1989,30(6):957-962
This is the first x-ray diffraction structural analysis of a dicoordinated phosphorus derivative with an N=P–O group, namely, the 2,6-di-tert-butylmethylphenyl ester of N-[2,4,6-tri(tert-butyl)phenyl]phosphenimidous acid (I) using Mo radiation and 6552 reflections to R=0.045. The unit cell parameters of the triclinic crystals are as follows: a=9.297, b=12.004, c=15.031, =107.87, =101.50, =95.50°, V=1542 Å3, d
calc
=1.1 g/cm3, Z=2, space group P
. The bond angle at the dicoordinated phosphorus atom is 110.3° and the PNC angle is 173.7°. The change in the hybridization of the nitrogen atom in I toward sp and the enhancement of the n
N
,
P–O
* interaction lead to shortening of the P=N and N–C bonds to 1.500 and 1.395 Å and elongation of the P–O bond to 1.658 Å. The steric strain in I leads to nonplanarity of the central group. The CNOP torsion angle is 86.3°, while the NPOC torsion angle is 169.2°.Part XLI, see ref. [1].Institute of Organic Chemistry, Academy of Sciences of the Ukrainian SSR. A. N. Nesmeyanov Institute of Heteroorganic Compounds, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 6, pp. 105–111, November–December, 1989. 相似文献
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Acetyl (Ia) and pivaloyl (Ib) triesters of the 1N,3N,5N-trihydroxy-1,3,5-triazin-2,4,6[1H,3H,5H]-trione (I) were synthesised. The spectrophotometric and potentiometric investigation of I revealed a weak acidic properties of triprotonic acid (pKa1=5.23, pKa2=6.32, and pKa3=7.93). The MS and TGA analyses of I indicated on hydroxyisocyanate as possible degradation product. The chelating ability of I with Fe(III)-ion was preliminary explored. IR measurements of aqueous solutions of I in the presence of Fe(III) ion showed the possible chelating ability of all hydroxamic moieties. The chemical structures and properties of investigated compounds were derived from the results of IR, 1H and 13C NMR, UV and MS spectrometric data, as well as thermogravimetric and potentiometric analysis. 相似文献
5.
A unique family of planar chiral symmetrical N-heterocyclic carbene precursors with restricted flexibility derived from [2.2]paracyclopane were obtained by a new synthetic route. The resolution of 4-amino-13-bromo[2.2]paracyclophane was achieved with relatively high efficiency. Starting from (4 S p,13 R p)-4-amino-13-bromo[2.2]paracyclophane, the planar chiral pseudogem-disubstituted [2.2]paracyclophanyl dihydroimidazoliums were prepared in a four-step sequence with good yields. The resulting dihydroimidazolium salts were fully characterized with a series of methods including single-crystal X-ray diffraction technique. 相似文献
6.
《Tetrahedron letters》2014,55(51):7072-7075
A simple and convenient three-step synthesis of 5-amino-substituted tetrazolo[1,5-a]-1,3,5-triazin-7-one sodium salts based on a fairly simple sequence of nucleophilic substitution of chlorine atoms in cyanuric chloride has been developed. The corresponding tetrabutylammonium salts were synthesized by cation-exchange with tetrabutylammonium chloride. The structures of the products were characterized by IR, 1H NMR and 13C NMR spectroscopy, and by elemental and X-ray analysis. 相似文献
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A convenient new synthesis of the ubiquitous environmental carcinogen benzo[a]pyrene (BaP) is described. In the key step, the method entails Suzuki coupling of naphthalene 2-boronic acid with 2-bromobenzene-1,3-dialdehyde and requires only three steps. It is considerably shorter and simpler than the older methods and provides BaP in higher overall yield. 相似文献
11.
Malcolm M. Campbell Veerappa B. Jigajinni Keith A. MacLean Richard H. Wightman 《Tetrahedron letters》1980,21(34):3305-3306
Bis[arylthio]methanes are produced in high yield on treatment of aryl chloromethyl sulphides with neutral alumina. 相似文献
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A. V. Shastin T. I. Godovikova B. L. Korsunskii 《Chemistry of Heterocyclic Compounds》1998,34(10):1195-1197
A study was carried out on electrophilic addition and hydrolytic dissociation of 2,4,6-tris[di(tert-butoxycarbonyl)methylene]hexahydro-1,3,5-triazine.
Chloro, bromo, and methyl derivatives of tris[di(tert-butoxycarbonyl)methyl]-1,3,5-triazine were synthesized for the first
time as well as 2,4,6-tris-(tert-butoxycarbonylmethyl)-1,3,5-triazine.
For Communication 1, see ref. [1].
N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow and Institute of Chemical Physics,
Russian Academy of Sciences at Chernogolovka, 142432 Chernogolovka, Moscow Oblast. Translated from Khimiya Geterotsiklicheskikh
Soedinenii, No. 10, pp. 1404–1407, October, 1998. 相似文献
14.
T. A. Tseitler G. V. Zyryanov D. S. Kopchuk I. S. Kovalev V. L. Rusinov O. N. Chupakhin 《Russian Journal of Organic Chemistry》2014,50(6):783-785
Direct arylation of 1,3,5-triazine-2,4(1H,3H)-dione with mesitylene afforded a novel fused heterocyclic system, 8,10-dimethyl-1,10b-dihydro[1,3,5]triazino[2,1-a]isoindole-2,4,6(3H)-trione. 相似文献
15.
Tomohisa Nagamatsu Keiichi Kinoshita Kenji Sasaki Taiji Nakayama Takashi Hirota 《Journal of heterocyclic chemistry》1991,28(2):513-515
A simple and highly efficient methodology for the synthesis of 1,2,4,5-tetrahydro[1]benzothiepino[4,5-e]-imidazo[1,2-c]pyrimidine ( XI ) having a novel ring system via 4-substituted 5,6-dihydro[1]benzothiepino-[5,4-d]pyrimidines VII-X is described. The anti-platelet aggregation activity for it and its related compounds against collagen-induced aggregation of rabbit blood platelets in vitro was found. 相似文献
16.
2-Triphenylphosphanimino-4-azidotetrazolo[5,1-a]-[1,3,5]triazine (6) was obtained by reaction of 2,4,6-triazido-1,3,5-triazine (1) with 1 equiv of triphenylphosphane. Raman and X-ray data revealed that only one azide group formed a tetrazole ring system whereas the second azide group did not undergo ring closure. To investigate the equilibrium between the tetrazole isomer and the open-chain azide structure for these and related species, (31)P NMR studies were carried out. The obtained spectra displayed an equilibrium between the tetrazole and the open-chain azide isomers. 2,4,6-Tris(triphenylphosphanimino)-1,3,5-triazine (4) was prepared by treatment of 1 with 3 equiv of triphenylphosphane, and its X-ray structure is discussed. On the basis of PM3 semiempirical and density functional calculations, the reaction of 1 with triphenylphosphane was studied. The thermodynamics of different isomerization reactions and the activation barriers to cyclization were estimated. 相似文献
17.
Jerald S. Bradshaw John T. Carlock Garren E. Maas 《Journal of heterocyclic chemistry》1975,12(5):931-935
s-Triazolo[4,3-b]pyridazine (I) photochemically reacted with cyclooctene, cyclododecene, bicyclo[2.2.2]oct-2-ene, bicyclo[2.2.1]hept-2-ene and indene to form tri and tetracyclic triazoles (II-X). Generally, two or more products were formed. For example the reaction with cyclooctene gave 4a,5,7,8,9,10,10a,11-octahydro-11-methylene-6H-cycloocta[4,5]-pyrrole[1,2-b]-s-triazole (II) and the corresponding 11-cyanomethyl product (III). When I was reacted with open chain alkenes, various isomers of the substituted pyrrolo[1,2-b]triazoles (XI-XV) were formed. Since the reaction was not stereospecific, cycloaddition must be a two step process. 相似文献
18.
Robert S. Klein Federico G. De Las Heras Steve Y-K. Tam Iris Wempen Jack J. Fox 《Journal of heterocyclic chemistry》1976,13(3):589-592
The synthesis of 3-methyl-7-oxo-5-thioxo-4H,6H-1,2,3-triazolo[1,5-a]-1,3,5- triazine (a new bicyclic system) is described. The key step involves reaction of 4-amino-5-methyl-1,2,3-triazole with carbethoxyisothiocyanate followed by cyclization with alkali. 相似文献
19.
2-Carbomethoxybenzoyl chloride reacted with some 5-methylamino-l-phenyl-3-R-pyrazoles to yield N-methyl-l-phenyl-3-R-pyrazol-5-yl)-2-carbomethoxybenzamides. These products were readily transformed into the corresponding acid, which in turn, refluxed in phosphorus oxychloride afforded the tricyclic system, l-phenyl-3-R-pyrazolo[3,4-b]benzazepine-4,9-dione. 相似文献
20.
Yoshihisa Kurasawa Harumi Arai Kiyoko Arai Atsushi Satoh Satoyuki Ninomiya Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1987,24(4):1219-1220
Novel 4-chlorophenylhydrazono-3-oxo-1,2,3,4-tetrahydropyridazino[3,4-b]quinoxalines 10a-c were synthesized by the cyclization of the α-hydrazonohydrazides 8a-c. The chlorination of 10a with phosphoryl chloride afforded 3-chloro-4-[2-(o-chlorophenyl)hydrazino]pyridazino[3,4-b]quinoxaline 12. 相似文献