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1.
A new synthetic route for the preparation of the betain-like compound (CH3N)6P4F8 from (CH3NPF3)2,N-methyl-hexamethyldisilazane andN,N-dimethyl-urea has been found. The steps of this multi-stage reaction could be rationalized to a far extent.
10. Mitteilung:Kubjacek M., Utvary K., Mh. Chem.112, 305 (1981).  相似文献   
2.
Amidrazone 1a and the tricarbonyl derivatives 2b-d reacted in boiling ethanol in the presence of 2,5-norbornadiene 5 giving the pyridine derivatives 6b-d respectively (59-72%) and in the presence of 2,3-dihydrofuran 7 yielding the lactones 10b-d (39-44%). The 2,2′-bipyridine derivatives 6e-g were similarly obtained in good yield (81-87%) from the reaction of amidrazone 1b and tricarbonyl derivatives 2b-d in the presence of 2,5-norbornadiene 5.  相似文献   
3.
Abstract

New dinaphthosulfide aza oxa thia crowns from 1-naphthol were prepared. At first, 2,2′-thiobis(1-hydroxynaphthalene) (a dinaphthol) was prepared from 1-naphthol. Then diester was prepared from the reaction of dinaphthol and methylchloroacetate. Aza crowns were synthesized from the reaction of diester and diamines (ethylene diamine, 1,3-diaminopropane, 1,4-diaminobutane, and 1,6-diaminohexane) in methanol.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

GRAPHICAL ABSTRACT   相似文献   
4.
A new synthesis of furo[3,4-b]quinolin-3(1H)-one derivatives has been established in straightforward fashion in high overall yields. An efficient Hendrickson reagent-initiated cascade annulation, which is composed of mild conversion of the stable amide precursor to the reactive imido-carbonium intermediate and subsequent intramolecular aza Diels-Alder reaction, successfully serves as the key reaction in the synthesis. Final oxidative cleavage of the carbon-carbon double bond of representative tricyclic precursor 8g led to completion of the synthesis of quinoline-lactone 2g in a high yield.  相似文献   
5.
6.
7-氮杂-3,6-二氧杂-二环[3.3.0]辛-2-酮类化合物合成的新方法   总被引:1,自引:0,他引:1  
5-甲氧基-2-(5H)-呋喃酮与氮酸硅烷基酯通过1,3-偶极环加成反应可以为7-氮杂-4-甲氧基-3,6-二氧杂-二环[3.3.0]辛-2-酮类化合物提供新的合成途径。通过元素分析、IR、^1HNMR、^13CNMR、MS等波谱分析进行了结构表征。  相似文献   
7.
高效液相色谱氮杂冠醚键合固定相的合成及性能研究   总被引:2,自引:0,他引:2  
我们曾用γ-氯丙基键合硅胶(CPS),在氢化钠(NaH)作用下合成了3-(氮杂-18-冠-6)丙基键合固定相(BCP)[1].该固定相对碱基、核苷酸、硝基苯酚等有较好的分离选择性,但由于NaH对硅胶基质腐蚀作用较大,导致BCP柱效及渗透性较低.本文采...  相似文献   
8.
A synthetic route to the pyrrolo[1,2‐a]indole ring system (benzannulated pyrrolizidine) involving a base‐induced intramolecular aza‐Michael reaction as the key C? N bond‐forming penultimate step, followed by a Cu‐catalyzed intramolecular α‐arylation reaction, to provide the tricyclic framework over six steps is described.  相似文献   
9.
A series of aza‐polycyles containing octahydroacridine core were prepared via an intramolecular aza‐Diels‐Alder reaction of a dimerized citral with various aromatic amines. This reaction is efficiently catalyzed by InCl3 at ambient temperature to afford the corresponding cyclized products in moderate to good yields.  相似文献   
10.
A new and convenient method for the preparation of 3,4‐dihydroquinazolines 5 with aryl and Ac groups at C(2) and N(3), respectively, has been developed. The key sequence is the formation of aza‐phosphorane intermediates by the reaction of N‐[2‐(azidomethyl)phenyl]benzamides 1 with Ph3P, followed by intramolecular aza‐Wittig reaction and 3‐acetylation, which can be conducted in one‐pot.  相似文献   
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