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81.
I. A. Nuretdinov I. P. Karaseva V. P. Gubskaya A. V. Il'yasov 《Russian Chemical Bulletin》1995,44(8):1486-1488
Cycloaddition of substituted 6,6-dimethyl-2-vinylnorpinenes with maleic anhydride occursvia the attack of a dienophile on diene from the less hindered side of the bicyclic fragment. IR, UV, CD, and1H NMR spectra of adducts have been studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1546–1548, August, 1995.The authors are grateful to I. E. Ismaev for recording several1H NMR spectra. 相似文献
82.
S. O. Bondareva V. V. Lisitskii N. I. Yakovtseva Yu. I. Murinov 《Russian Chemical Bulletin》2004,53(4):803-807
The kinetics of hydrolysis of 1,2-disubstituted imidazolines in aqueous media was studied (pH 2.0—12.5, T = 25—90 °C) by UV spectroscopy. The hydrolysis products were identified. The introduction of a branched substituent into position 2 of the imidazoline ring increases the hydrolytic stability of the compounds. The effect of the pH on the hydrolysis rate of imidazolines is discussed. 相似文献
83.
V. Ya. Sosnovskikh M. A. Barabanov B. I. Usachev R. A. Irgashev V. S. Moshkin 《Russian Chemical Bulletin》2005,54(12):2846-2850
Condensation of 4-acetyl-5-hydroxy-3-methyl-1-phenylpyrazole with RFCO2Et (RF = CF2H, CF3) in the presence of LiH affords 4-di(tri)fluoroacetoacetyl-5-hydroxy-3-methyl-1-phenylpyrazoles from which 6-di(tri)fluoromethyl-and
5-di(tri)fluoroacetyl-3-methyl-1-phenylpyrano[2,3-c]pyrazol-4(1H)-ones were synthesized. The reactions of pyrano-pyrazoles with hydrazine hydrate, ethyl mercaptoacetate, or aromatic amines
proceed at the C(6) atom with pyrone ring opening and formation of aminoenones, pyrazoles, or thiophenes with the 5-hydroxy-3-methyl-1-phenyl-4-pyrazolyl
fragment.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2750–2754, December, 2005. 相似文献
84.
Paramasivan Halasyamani Kevin R. Heier Michael J. Willis Charlotte L. Stern Kenneth R. Poeppelmeier 《无机化学与普通化学杂志》1996,622(3):479-485
Crystals of CuNb(pyz)2OF5 · (pyz)(H2O) ( 1 ) and [Cu(pyz)2.5]+ [NbF6]? · (pyz) ( 2 ) were grown (150°C and autogeneous pressures) from CuO, 1/2(Nb2O5), (HF)x · pyridine, and H2O in excess pyrazine. Light blue single crystals of ( 1 ) are orthorhombic, crystallizing in space group Cccm (No. 66), with a = 14.547(1) Å, b = 16.135(2) Å, c = 13.803(2) Å, and Z = 8. The structure of ( 1 ) contains corner shared [Cu(pyz)4/2F2/2]+, [Cu(pyz)4/2O2/2], and [NbF4O1/2F1/2]?0.5 octahedra. Orange crystals of ( 2 ) are monoclinic, crystallizing in space group C2/c (No. 15), with a = 11.792(8) Å, b = 17.123(3) Å, c = 17.051(5) Å, β = 90.04(4)°, and Z = 8. The structure of ( 2 ) contains puckered rings of corner shared [Cu(pyz)(pyz)3/2]+ tetrahedra and isolated [NbF6]? anions within the rings. 相似文献
85.
V. I. Terenin E. V. Kabanova N. A. Tselishcheva A. S. Ivanov N. V. Zyk 《Chemistry of Heterocyclic Compounds》2007,43(8):1038-1043
A study was carried out on the reaction of pyrrolo[1,2-a]pyrazines containing an alkyl, aryl, or aralkyl substituent at C-1
with trifluoroacetic anhydride. Trifluoroacetylation products may be formed either by reaction in the pyrrole ring or at the
aryl or aralkyl groups at C-1. Products of electrophilic substitution at C-6 are formed in the trifluoroacetylation of pyrrolo[1,2-a]pyrazines
containing at C-1 a substituent bulkier than a methyl group but lacking substituents at C-6 (the α-position of the pyrrole
ring).
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1226–1233, August, 2007. 相似文献
86.
87.
固定有四硫富瓦烯.四氰基奎诺二甲烷的杂聚吡咯膜微葡萄糖电极 总被引:1,自引:0,他引:1
铂比互铂化处理后,形成疏松,粗糙的表面,将四硫富瓦烯-四氰基奎诺二甲烷导电有机盐入到铂化的铂黑微粒中。将3-羰基丁酸吡咯与吡咯按适当的比例在其表面用电化学聚合方法,将葡萄糖氧化酶固定于聚合形成的杂聚膜中制成微酶电极。该微酶电极测定时几乎不受氧分压影响,灵敏度高,响应快。 相似文献
88.
一种新型吡嗪铱(Ⅲ)配合物的合成及其磷光性质 总被引:2,自引:0,他引:2
利用5-甲基-2,3-二苯基吡嗪(MDPP)和水合三氯化铱(IrCl3•H2O),合成了一种新型吡嗪铱配合物Ir (MDPP)2 (acac).通过1H NMR、元素分析和质谱方法对配合物结构进行了表征,并研究了配合物的吸收光谱和光致发光光谱.结果表明,配合物Ir (MDPP)2(acac)在393和528 nm处存在单重态1MLCT(金属到配体的电荷跃迁)和三重态3MLCT的吸收;在588 nm 处有较强的金属配合物三重态的磷光发射,是一种绿色磷光材料. 相似文献
89.
We have developed a method for obtaining 2-substituted 3-amino-6,6-dimethyl-5,6-dihydro-8H-pyrano[4′,3′:4,5]-and 5,6,7,8-tetrahydrobenzo[b]thieno[2,3-d]pyrimidin-4(3H)-ones,
converted by deamination to the corresponding dihydropyranothieno-3H-pyrimidinones.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 441–444, March, 2006. 相似文献
90.
A substituted polyacetylene bearing a furan ring, poly(2-propynyl 2-furoate) (PPF), was synthesized for the first time with palladium acetylide complex catalysts in CHCl3 at 60℃ to give a soluble and stable polymer with a yield of ca.75%. Some features for polymerization of 2-propynyl 2-furoate are described and discussed. The resulting polymer was characterized by IR, GPC and ^1H-NMR analysis. 相似文献