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1.
以氯化血红素(Ⅰ)为原料,经过溴化氢-冰醋酸加成反应、羟基亲核取代反应和无水氯化氢催化酯化反应制得3,8-双-(1-羟基乙基)次卟啉二甲酯(Ⅲ),然后通过琼斯试剂氧化反应制备了3,8-双乙酰基次卟啉二甲酯(Ⅳ)。 考察了血红素与溴化氢-冰醋酸饱和溶液反应过程中温度和时间对3,8-双-(1-羟基乙基)次卟啉二甲酯(Ⅲ)产率的影响;改进了酯化反应的实验条件;选用了廉价易得、选择性较好的羟基选择性氧化剂。 实验结果表明,当反应温度为35 ℃、反应时间为25 h时,血卟啉(Ⅱ)的产率最高,为98.5%;当催化剂为无水氯化氢时产物(Ⅲ)的产率最高,为72.1%;使用琼斯试剂做氧化剂使实验成本大大降低。 通过1H NMR、MS和IR测试技术对产物结构进行了表征。  相似文献   

2.
In an alkaline medium, 3,4-dihydropyridin-2(1H)-ones form 2,7-diazebicyclo[2.2.2]-octane-3,8-diones, which are thiolated to the corresponding dithiones. The alkylation of the last proceeds at the sulfur atoms with the formation of 2,7-diazabicyclo[2.2.2]octa-2,7-dienes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 620–625, May, 1989.  相似文献   

3.
Three-component condensation of formaldehyde, o-phenylenediamine, and ethylenediamine gave for the first time 4,5-dihydro-1,6:3,8-dimethano-1,3,6,8-benzotetrazecine. Its structure was proved by X-ray diffraction analysis. A similar condensation of formaldehyde with a mixture of ethylenediamine and 1,2-diamino-4-methylbenzene yielded 10-methyl-4,5-dihydro-1,6:3,8-dimethano-1,3,6,8-benzotetrazecine and a condensation with a mixture of o-phenylenediamine and propane-1,2-diamine yielded 4-methyl-4,5-dihydro-1,6:3,8-dimethano-1,3,6,8-benzotetrazecine. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1544–1546, July, 2008.  相似文献   

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Conclusions The hydrosilylation of pentamethylvinylcyclotrisiloxane by hydromethylphenylcyclotetrasiloxanes gives new bicyclosiloxanylethanes. In the presence of basic initiators, these compounds form cross-linked polymers.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 241–244, January, 1986.  相似文献   

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Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, p. 1707, July, 1991.  相似文献   

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Freshly prepared solutions of disodium ditelluride react with diiodobutane to give small yields of 1,2-ditellurane. In contrast, reactions of α,α-bis(chloromethyl)-o-xylene and phthaloyl chloride give 3,4-benzo-1-telluracyclopentane and tellurophthalic anhydride respectively.  相似文献   

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Summary A convenient method for the preparative synthesis of 1,2-diacetylcycloalkanes was developed; the starting materials are readily accessible acetylcycloalkenes.  相似文献   

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A route to cyclic peroxides containing 1,2-dioxolane, 1,2-dioxane or 1,2-dioxepane rings is described. These compounds present simpler structures related to the bicyclic core of stolonoxides, metabolites with marked cytotoxicity against several mammalian tumor cell lines, isolated from the marine tunicate Stolonica socialis. The key synthetic step consists in the intramolecular Michael addition of a secondary hydroperoxide group to an α,β-unsaturated ester.  相似文献   

13.
[reaction: see text] The reactions of the lithium (S)-alpha-(methylthio)-2-(p-toluenesulfinyl)benzyl carbanion with (S)-N-p-tolylsulfinyl aldimines evolve in a completely stereoselective manner providing a one-step synthesis of enantiomerically pure anti-1,2-disubstituted 1,2-amino sulfide derivatives.  相似文献   

14.
A synthesis of 1,2-cis-configurated, non-isosteric phosphonate analogues of aldose-1-phosphates is described. Treatment of 1-O-acyl-glycoses 1 , 7 , 13 , and 19 with trialkyl phosphite in the presence of trimethylsilyl trifluoromethanesulfonate gave the 1,2-cis-configurated glycosylphosphonates 2 , 4 , 8 , 10 , 14 , 16 , 20 , and 22 as the major anomers and the 1,2-trans-configurated glycosylphosphonates 3 , 5 , 9 , 11 , 15 , 17 , 21 , and 23 as the minor anomers. The 1,2-cis-configurated phosphonates 4 , 10 , 16 , and 22 were deprotected to give the (β-D -glucopyranosyl)phosphonate 6 , the (β-D -mannopyranosyl)phosphonate 12 , the (β-D -ribofuranosyl)phosphonate 18 , and the (β-D -arabinofuranosyl)phosphonate 24 , respectively, in high yields. The preferred formation of 1,2-cis-configurated phosphonates is explained by postulating an equilibrium between the anomeric phosphonium-salt intermediates (such as 25 and 26 ) and a stabilization of the cis-configurated salts through formation of a pentacoordinated species (such as 28 ).  相似文献   

15.
Reactions of lithiated heteroaryl- (or aryl-) methylbenzotriazoles 4a-e with heteroaryl (or aryl) esters 5a-f give alpha-benzotriazolyl ketones 6a-n in average yields of 90-95%. Oxidation of ketones 6a-l in aqueous DMSO in the presence of oxygen and sodium bicarbonate gave heteroaryl- (aryl-) 1,2-ethanediones 7a-l in average yields of 60-80%.  相似文献   

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A new route is outlined for preparation of vinyl 1,2-diketones via a three-step sequence. First, allylic alcohols are photooxidized by 1O2 to hydroperoxides, which are reduced to vinyl 1,2-diols. These vinyl 1,2-diols are oxidized to vinyl 1,2-diketones with oxoammonium salts, which are prepared in situ from organic nitroxyl radicals. The new route is short, avoids the use of protecting groups, and is generally applicable to obtain aliphatic or aromatic vinyl 1,2-diketones.  相似文献   

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1,2-Difluoro-1,2-bis(pentafluorophenyl)dichlorane is a new class of organic polyvalent chlorine compound. The closeness of the retention time of this compound and that of chloropentafluoro- benzene made its purification difficult. All attempts to obtain this compound in high yield have failed. 1,2-Difluoro-1,2-bis- (pentafluorophenyl)dichlorane is prepared by fluorination of chloropentafluorobenzene at 128°C with elemental fluorine. It has been characterized by 19F n.m.r., i.r., mass spectroscopy and elemental analysis.  相似文献   

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