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41.
Yang KH Liu YC Yu CC Chen BC 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,82(1):383-388
New Hofmann type clathrates in the form of M(pp)2Ni(CN)4·2G (where pp = 1-phenylpiperazine, G = 1,4-dioxane and M = Ni, Co or Cd) have been prepared in powder form and their FT-IR and FT-Raman spectra are reported. The results suggest that the present compounds are similar in structure to the Hofmann type clathrates and their structures consist of conjugated polymeric layers of |M–Ni(CN)4|∞ with the pp bound to the metal (M) atom. 相似文献
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The design and synthesis of two aromatic amines with dendritic structures, i.e. 3,4,5‐tribenzyloxyaniline (3,4,5‐G1‐NH2) and 2,5‐dibenzyloxyaniline (2,5‐G1‐NH2), were conducted. A coupling reaction of three or two equivalents of benzyl bromide to one equivalent of methyl hydroxybenzoate generated methyl 3,4,5‐tribenzyloxybenzoate (3,4,5‐G1‐COOCH3), methyl 2,5‐dibenzyloxybenzoate (2,5‐G1‐COOCH3) and 2,6‐dibenzyloxybenzoate (2,6‐G1‐COOCH3) in high yields. All G1‐COOCH3 derivatives were studied by X‐ray analysis. The results show that these dendrons have sufficient volume to be used as the fine ligands for certain catalysts. The amide intermediates (benzamide, G1‐CONH2) were obtained by reaction between ammonia and G1‐COOCH3. Interestingly, 2,6‐dibenzyloxybenzamide (2,6‐G1‐CONH2) can not be prepared in the same condition, which may be due to the overlarge steric block. Sodium hypochlorite was an effective oxidant to generate methyl carbamates G1‐ NHCO2CH3. 相似文献
43.
Ahmed M. Farag Hamdi M. Hassaneen Ikhlas M. Abbas Ahmad S. Shawali Mohamad S. Algharib 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):243-249
Abstract 2-(Thiocyanatoacetyl)thiophene 2 and its selenium analog 3 couple with diazotized anilines and yield 3-aryl-2-imino-5-(2-thenoyl)-2,3-dihydro-1,3,4-thiadiazoles 6 and 3-aryl-2-imino-5-(2-thenoyl)-2,3-dihydro-1,3,4-selenadiazoles 7 respectively. The reactions of both 6 and 7 with nitrous acid, acetic anhydride and benzoyl chloride are described. Azo coupling of 2-amino-4-(2-thienyl)thiazole 17 and its selenazole analog 18 with diazotized anilines yielded the arylazo derivatives 19 and 20 respectively. Reaction of the hydrazidoyl bromide 16 with potassium thiocyanate, potassium selenocyanate, thiourea and selenourea yields 6, 7, 19, and 20 respectively. 相似文献
44.
Synthetic rubbers help to solve severe problems in rubber‐technology arising from the sensitivity natural rubber shows towards UV‐radiation (e.g. sunlight), heat, and ozone: For this reason more than half of the rubber demand nowadays is satisfied by the chemical industry. However, synthetic rubbers are superior to its natural counterpart not only in regard to their ageing resistance and robustness towards several chemicals: They can easily be adapted to new challenges born by a more and more demanding technology – e.g. using improved concepts in the design of rubber molecule architectures, new catalysts or post‐polymerization altering of the elastomers. These challenges demand for a deep and clear understanding of rubber's chemistry and physics. 相似文献
45.
J. Sepúlveda-Arques Eugenia Gonzalez Rosende Dolores Perona Marmol Elena Zaballos García B. Yruretagoyena J. Ezquerra 《Monatshefte für Chemie / Chemical Monthly》1993,124(3):323-325
Summary
Trans-2-aryl-3-hydroxymethyl-1-methylpyrrolidines suffer an unusual Hofmann elimination when treated withp-toluensulfonyl chloride in basic medium at room temperature.
Ungewöhnliche Hofmann-Eliminierung bei niederer Temperatur. Die Reaktion von 3-Hydroxymethylpyrrolidinen mitp-Toluolsulfonylchlorid (Kurze Mitt.)
Zusammenfassung Trans-3-hydroxymethylpyrrolidine erleiden in basischem Medium bei Behandlung mitp-Toluolsulfonylchlorid eine ungewöhnliche Hofmann-Eliminierung.相似文献
46.
采用1-氨基蒽醌经酰氯化,合成含双键的单体,再与丙烯酰胺单体共聚,随后对共聚物进行了Hofmann反应,制得含伯胺侧基和蒽醌生色团的水溶性聚合物.利用傅立叶红外光谱、核磁共振氢谱及紫外,可见光等测试手段对所合成的聚合物的结构进行了表征,并探讨了含蒽醌生色团的水溶性聚合物的光致电子转移性能. 相似文献
47.
Substituted (±)-trans-1-benzyl-6-oxo-2-phenylpiperidine-3-carboxamides (type I) and the acylated derivatives of (±)-trans-5-amino-1-benzyl-6-phenylpiperidin-2-one (type II) were prepared by the reaction of (±)-trans-1-benzyl-6-oxo-2-phenylpiperidine-3-carboxylic acid and some common reagents to provide the products in satisfactory yields. Newly synthesized compounds share the same moiety with common SP antagonists and thus similar activities might be expected. 相似文献
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2-(4-Methoxyphenyl)-1-oxo-1,2-dihydro-1,6-naphthyridine-4-carboxamide (4c) underwent Hofmann rearrangement with iodobenzene diacetate in methanol to give the corresponding 4-amino compound (6c). This, when reacted with 2,4-pentanedione and then hot phosphoryl chloride (attempted Combes synthesis) gave a new heterocyclic system, 6-(4-methoxyphenyl)-2-methylpyrido[3,2-c]pyrrolo[2,3-e]azocin-7(6H)-one (9c). This showed typical pyrrole-type reactivity at the 3-position. Alternatively, an attempt to convert the 4-NH2 in 6c to 4-OH by diazotization gave, instead, a [1,2,3]triazolo[1,5-a]pyridine-3-carboxaldehyde (16c). The same series of reactions on a benzo analog, 2-methyl-1-oxo-1,2-dihydrobenzo[b][1,6]naphthyridine-4-carboxamide (4a), gave the same results. 相似文献