首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 171 毫秒
1.
由(+)-2-氨基丁醇合成氮杂手性冠醚   总被引:2,自引:0,他引:2  
赵冬  尹承烈 《有机化学》1991,11(3):310-313
手性冠醚由于具有手性识别和不对称催化有机反应的性质而受到人们的重视,有关它们的合成及性质,已很多论述。氮杂冠醚则是合成穴醚、双冠醚、套索冠醚(LariatEther)等的重要中间体,也可与高分子材料(高分子载体或高分子基质)连接,用于有机化合物的色谱分离。氮杂手性冠醚兼备手性和氮杂冠醚两种特性,而可能具有广泛的用途。  相似文献   

2.
合成了一种新的双冠醚,氧化偶氮双苯并15-冠-5。初步探讨了它的光异构现象及其对稀土和碱金属离子的萃取能力。  相似文献   

3.
邻苯二酚、3,5-二叔丁基邻苯二酚分别与1,5-二氯-3-氧(杂)戊烷在碱性条件下反应, 合成了开链冠醚化合物(1a-b)。1a-b与环氧氯丙烷在氢氧化钠正丁醇中缩合, 得到相应的6-羟基二苯并-16-冠-5(2a-b)。化合物2a-b分虽与丁二酰氯、壬二酰氯在无水苯中反应, 生成了两种新的酯型双冠醚化合物3a-b; 2a-b分别与1,3-二溴丙烷、1,4-二溴丁烷、1,5-二溴戊烷、1,8-二氯-3,6-二氧(杂)辛烷及1,11-二氯-3,6,9-三氧(杂)十一烷在无水二氧六环中反应, 得到了四种新的醚型双冠醚化合物4a-e。  相似文献   

4.
邻苯二酚、3,5-二叔丁基邻苯二酚分别与1,5-二氯-3-氧(杂)戊烷在碱性条件下反应, 合成了开链冠醚化合物(1a-b)。1a-b与环氧氯丙烷在氢氧化钠正丁醇中缩合, 得到相应的6-羟基二苯并-16-冠-5(2a-b)。化合物2a-b分虽与丁二酰氯、壬二酰氯在无水苯中反应, 生成了两种新的酯型双冠醚化合物3a-b; 2a-b分别与1,3-二溴丙烷、1,4-二溴丁烷、1,5-二溴戊烷、1,8-二氯-3,6-二氧(杂)辛烷及1,11-二氯-3,6,9-三氧(杂)十一烷在无水二氧六环中反应, 得到了四种新的醚型双冠醚化合物4a-e。  相似文献   

5.
双冠醚PVC膜钾电极的研究   总被引:2,自引:0,他引:2  
Kimura等报道了双冠醚,庚二酸二-[3,4-(1’,4’,7’,10’,13’-五氧杂环十五-2-烯)骈苄酯](简称双冠醚A),并用作钾离子选择性电极的活性物质。朱春生等最近报道了双冠醚B的合成。本文研究了上述两种双冠醚作为电活性物质的PVC膜钾离子选择性电极,并与目前以二叔丁基二苯骈-30-冠-10为电活性物质的PVC商品钾电极作对比,实验结果说明双冠醚钾电极在测量范围,对Na~+,NH_4~+等离子的选择性系数,pH范围等方面均优于商品电极。  相似文献   

6.
双冠醚化合物对某些金属离子比单冠醚具有更好的络合性能和选择性,它们合成、应用研究越来越受到人们的重视,本工作采用2,6-二羟甲基对甲氧基苯酚为缩合剂与芳香族冠醚缩聚,得到一系列具有双冠醚结构特征的新酚醛型聚苯并冠醚(简称聚冠醚),聚冠醚合成容易,并呈现了比相应单冠醚更优越的络合萃取能力和富集效率。  相似文献   

7.
Kimura等曾报道了含有苯并15-冠-5和苯并18-冠-6的双冠醚双酯化合物,并用作钾离子选择电极,其性能优于单冠醚制成的钾离子选择电极.黄德培等报道了4-羟甲苯并-15-冠-5的庚二酸酯(简称双冠醚A)和双冠醚B作为电活性物质的PVC膜钾离子选择性电极,在测量范围,对Na~+,NH_4~+等离子的选择性系数、pH范围等方面均优于以二叔丁基二苯并30-冠-10为活性物质的商品钾电极. 为了更广泛地探索双冠醚化合物的应用前景,本文报道新的双冠醚双酯化合物3a~3f的合成.即以邻苯二酚与ββ’二氯乙醚缩合得二(2-邻羟基苯氧基乙基)醚(1),1与环氧氯丙  相似文献   

8.
腙型双冠醚对碱金属的配位性能   总被引:1,自引:1,他引:1  
本文报道了五个腙型双冠醚的合成。电导测定结果表明含苯并-15-冠-5单元的双冠醚与四苯基硼酸钾、铷、铯,含苯并-18-冠-6单元的双冠醚与四苯基硼酸铯生成2:1夹心型配合物(冠醚单元:金属离子)。并用这些双冠醚的氯仿溶液萃取苦味酸碱金属盐水溶液,测定了萃取百分率和计算了萃取平衡常数,结果表明腙型双冠醚的萃取能力及选择性优于相应的单冠醚。  相似文献   

9.
报道了"一锅法"合成含两种桥联链的新型杯[4]双冠醚和双杯[4]冠醚.杯[4]芳烃先与N,N’-乙撑基-二(2-氯乙酰胺)发生"1+1"缩合反应,然后直接加入三甘醇双对甲苯磺酸酯继续进行"2+2"缩合反应,合成了含两种桥联链的新型双杯[4]冠醚4.按照相似程序,杯[4]芳烃先后与N,N’-乙撑基-二(2-氯乙酰胺)、溴乙酸乙酯和二乙烯三胺反应,得到含两种桥联链的新型杯[4]双冠醚5.化合物5进一步与异硫氰酸苯酯反应合成带硫脲支链的杯[4]双冠醚6.所有新化合物的结构与构象经元素分析、质谱、核磁共振谱等表征证实.  相似文献   

10.
一些酯型、醚型、Schiff硷型和亚苯基二氧亚甲基等桥联的双冠醚钾离子电极的响应特性已经报道。本文报道12种酮型、醇型和烃型双(4′-苯并-15-冠-5)PVC膜钾离子选择电极的性能。  相似文献   

11.
苯甲醛和对氯苯甲醛在碱存在下分别与4′-乙酰基苯并-15-冠-5缩合,生成冠醚化查尔酮1a和1b。此二化合物作为中间体进一步与4′-乙酰基苯并-15-冠-5发生Michael反应,生成两种酮型双冠醚2a和2b。  相似文献   

12.
The concept of bisthioxanthylidene biscrown ethers as potential stereodivergent chiral ligands in asymmetric synthesis is introduced. Substituted bisthioxanthylidenes may be chiral and can exist as stable enantiomers due to their folded structure. As a result, both a right-handed helix (P) and left-handed helix (M) are present in this type of molecule. This offers the unique possibility to construct two crown ether moieties, attached to the same molecule, of which one exhibits (P)-helicity and the other (M)-helicity. When the crown ether moieties differ in size they can be complexed selectively with a base containing a cation of appropriate diameter. In this manner the (P)-helix and the (M)-helix can be activated selectively to serve as a chiral environment for base catalyzed asymmetric synthesis. Thus, we envisioned the new concept of a single chiral ligand to separately synthesize two enantiomers of a chiral product just by varying the added base. For this purpose, four new bisthioxanthylidene monocrown ethers and two new bisthioxanthylidene biscrown ethers were synthesized. Two biscrowns and two monocrowns were separated into their respective enantiomers (HPLC) and optical data (UV and CD) were collected to ensure stability of enantiomers at ambient temperatures. Ion complexation of one mono- and two biscrown ethers with potassium and sodium cations was investigated.  相似文献   

13.
用脂链或芳环桥联两个苯并—15—冠—5单元的双冠醚报道较多,而桥联苯并-18-冠-6或苯并-12-冠-4单元的双冠醚报道较少。本文报道以α,ω-二卤代烷或二(对甲苯磺酸)二甘醇酯与邻羟基苯甲醛反应,制成相应的二醛化合物1_(α-∫)后使它们分别与4′-氨基苯并-18-冠-6或4′-氨基苯并-12-冠-4反应,得到脂芳混合桥联的schiff碱型双冠醚2_(b-∫)或3_(?)。  相似文献   

14.
本文报导了在文献[1]基础上合成的含三嗪环的双冠醚[2](简称双冠醚C)所研制成的双冠醚C钾、铊离子选择电极.实验和应用表明,其电极性能优良.  相似文献   

15.
Two novel biscrown ethers with rigid cis/trans ethylene linker were synthesized via Wittig reaction in high yield (about 80%). Their pure cisltrans-isomers were obtained by column chromatography separation. And their structure/configuration was confirmed by ^1H NMR,^ 13C NMR, ESI mass spectrum, elemental analysis and UV-vis speca'a.  相似文献   

16.
本文总结了饱和漆酚双冠醚电子电离质谱的裂解规律。十个测试样品的结构均为二个芳香冠醚通过NHCORCONH对称桥连而成。当R为烷基时,裂解首先发生在酰胺键或其邻近的键上。R为芳基时则在分子的冠醚部份首先发生裂解。文中还叙述了在某些化合物中的特殊的氢重排反应。  相似文献   

17.
Macrocyclic ligands have been prepared by various one‐step cyclooligomerization processes. This short review covers one‐step cyclization reactions involving the formation of four to twenty or more new covalent bonds. The new macrocycles reviewed include cyclophanes, biscrown ethers, cryptands, macrolides, cage compounds, calixarenes, homocalixarenes, cucubiturils, and supercryptands all prepared by one‐step syntheses.  相似文献   

18.
苯甲醛和对氯苯甲醛在碱存在下分别与4'-乙酰基苯并-15-冠-5缩合, 生成冠醚化查尔酮1a和1b. 此二化合物作为中间体进一步与4'-乙酰基苯并-15-冠-5发生Michael反应, 生成两种酮型双冠醚2a和2b.  相似文献   

19.
C-silyl enol ethers or thioenol ethers have been prepared by a Peterson reaction, as intermediates for acylsilane synthesis. Bis(trialkylsilyl)(methoxy)- or -(methylsulfanyl)methanes bearing identical or different trialkylsilyl groups were used as starting materials in order to assess the selectivity of the Peterson elimination step. A good selectivity was observed only with ethers bearing the TMS and TBDMS groups. However, there is no practical interest to use such reagents owing to the difficulty to obtain them in correct yields. Bis(trimethylsilyl)(methylsulfanyl)methane proved to be a good reagent for the preparation of C-silyl thioenol ethers, which are hydrolyzed under classical acid conditions to give acylsilanes in fair overall yields. This convenient procedure was extended to the synthesis of bis(acylsilanes).  相似文献   

20.
A series of calix[4]arene-bis-crownethers were synthesized in a fixed 1,3-alternateconformation with good yields by the reaction of amonocyclic calixcrown ether with multi-ethyleneglycoldi-p-toluenesulfonate in the presence of cesiumcarbonate. In the preparation of the monocycliccalixcrown ethers (1 and 2), the use ofpotassium carbonate as a base provided the best yieldregardless of the template concept. In two phaseextraction and competitive transport experiments forligand-metal complexation, calix[4]arene biscrown(5) provided the best selectivity for potassiumion. When a calixbiscrown ether (4) bearingdifferent sized crown ether loops coordinates to K+and Cs+, respectively, the changes of peak splittingpatterns and chemical shift on 1H NMR spectra aredependent on the complexed metal ion species.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号