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1.
王国芝  胡继文 《广州化学》2010,35(2):23-26,30
在室温下,二氟溴甲基膦酸二乙酯与锌粉反应生成锌试剂;2,4-二硝基氯化苄与合成的锌试剂在溴化亚铜催化作用下即可反应生成二硝基苯乙基(氟代)磷酸二乙酯化合物。两步反应都可在室温下进行,操作简单易行。  相似文献   

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Russian Journal of General Chemistry -  相似文献   

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A simple method for the preparation of phosphorus-containing pyrimidine analogues such as 2,5-dihydro-2-ethoxy-1,5,2-diazaphosphinine 2-oxides 9, 12-15 and adducts 3, 10 is described. Dihydrophosphinines 9, 12-15 are prepared from primary enamine phosphonates and nitriles or from phosphonates and nitriles in the presence of base, while highly stable hydrogen-bonded amine-dihydro-diazaphosphinine adducts 3, 10 are obtained by the addition of amine to dihydrophosphinines 9 or by reaction of alkylphosphonates with nitriles in the presence of LDA.  相似文献   

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Intramolecular Wittig reaction is extended to the synthesis of 1-perfluoroalkynyl phosphonates.  相似文献   

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2-Amino-3-(-phthalimidoalkyl)indoles have been obtained by the rearrangement of -phthalimido acid -phenylhydrazides under the action of POCl3. The possibility has been studied of eliminating the phthalyl protective group from these compounds and a convenient method has been developed for obtaining 2-amino-3-(-aminoalkyl)indole dihydrochlorides. The behavior of the 2-amino-3-(-phthalimidoalkyl) indoles in alkylation reactions has been investigated.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 484–488, April, 1980.  相似文献   

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Conclusions A method has been developed for the preparation of gem-disubstituted butenylamine derivatives of cyclobutane, cyclopentane, and cyclohexane by the allylborylation of Schiff bases (imines).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1179–1182, May, 1989.  相似文献   

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A simple and catalyst-free method for the synthesis of phosphonated 2(1H)-pyrazinones is described starting from 3,5-dichloropyrazinones. The method also works for 3-bromo- and 3-iodopyrazinones. Classical heating conditions as well as microwave-enhanced reaction conditions were tested.  相似文献   

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A diastereomeric mixture of dimethyl (2-formyl-2-methyl-1-phenylcyclopropyl)phosphonate ((Z)-6, (E)-6) was obtained by thermally induced cyclopropanation of α-methylacrolein with α-diazobenzylphosphonate 5. Application of proline or proline-derived organocatalysts accelerated the reaction, but had a minor effect on the Z/E ratio of 6. By reaction with benzylamine or methyl esters of glycine, (S)-alanine, and (S)-phenylalanine, the Z/E-mixture of 6 was converted into cyclopropylaldimines, which after reduction gave the corresponding N-substituted (2-aminomethyl-cyclopropyl)phosphonates.  相似文献   

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The Ritter reaction of enantiopure 2-(1-aminoalkyl)aziridines 1 with different nitriles afford enantiopure tetrasubstituted imidazolines 2. The opening of the aziridine ring takes place with total regio- and stereoselectivity. A mechanism to explain the described addition reaction is proposed. [reaction: see text]  相似文献   

15.
The eight (arylalkyl)‐modified phosphoramidites (=(arylalkyl)phosphonamidites) 1 – 8 (Fig. 2) were synthesized (Schemes 13) and incorporated at different positions into 2′‐deoxyoligonucleotides. The [P(R)]‐ and [P(S)]‐diastereoisomers of the hexanucleotides 32 – 39 (Table 1) and of the dodecanucleotides 41 – 45 (Table 2) obtained were separated by means of reversed‐phase HPLC. UV, CD, and fluorescence spectroscopy were used to investigate the thermal stability (Tm) and the structural changes of their DNA duplexes with 5′‐d(CGCGCG)‐3′ and 5′‐d(ATGATTGACCTG)‐3′, respectively. The Tm values significantly depend on the place of modification (Table 2). A dangling‐end effect is observed when the [3‐(anthracen‐9‐yl)propyl]‐modified 8 is attached at the 5′‐terminus (see duplex with 45c ). In the case of the incorporation of aromatic moieties tethered via a methylene linker to the P‐atom (benzyl‐ and (naphthalen‐1‐ylmethyl)‐modified 1 and 6 , resp.), the duplexes with the [P(R)]‐oligonucleotides are more stable than those with the [P(S)]‐isomers, whereas in the case of longer alkyl chains at the P‐atom (see 2 – 5 ), the Tm values show the reverse tendency. The observed Tm differences are assigned to changes in base stacking (Figs. 6 and 7).  相似文献   

16.
Optically pure methyl, ethyl, isopropyl, and benzyl (R)-malolactonate were prepared from (S)-(-)-malic acid and were polymerized in the bulk with tetraethylammonium benzoate as the initiator to yield high-molecular-weight, crystalline polymers. The optical purity of methyl and benzyl malolactonate was determined by 1H NMR spectroscopy of the β-lactone complexed with a chiral europium shift reagent. Enantiomeric excesses of 100% were found (the experimental error was 3%). Optically active poly(β-malic acid) was obtained from optically active poly[benzyl (S)-malate] by catalytic hydrogenolysis of the pendent benzyl esters. Ethyl and benzyl (R)-malolactonate were also copolymerized, and the benzyl esters of the resulting copolymer were converted into carboxylic acid units by hydrogenolysis.  相似文献   

17.
Summary The conformation and relative configuration of [1-(2H-azirin-2-yl)alkyl]phosphonates (2) has been established by thorough investigation of some characteristic representatives of the series by1H,13C,15N, and31P NMR spectroscopy. It is shown that the chemical shift of the proton located to the phosphonate group can be used as a criterion for the discrimination and stereochemical assignment of diastereoisomers. NMR spectroscopic features of the compounds are discussed in terms of structural relationships.Dedicated to Univ.-Prof. Dr.K. Schlögl with the best wishes to his 70th birthday  相似文献   

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Conclusions We have developed a preparative method for the synthesis of the formerly unknown tetrakis (alkyl,aryl)sulfonylethenes, including the oxidation of tetrakis (alkyl,aryl) thioethenes by trifluoroperacetic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2327–2330, October, 1982.For preliminary discussion, see [1].  相似文献   

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