Template Effects. 2.1Convenient Syntheses of Crown Ethers Promoted by Ba++Ion in Aqueous Solution
- 1 January 1979
- journal article
- research article
- Published by Taylor & Francis in Synthetic Communications
- Vol. 9 (9) , 851-856
- https://doi.org/10.1080/00397917908064203
Abstract
The current interest in the preparation of crown ethers is due to their extensive application in many different areas.2 Published synthetic procedures3 that have appeared since Pedersen's first report4 are based mostly on the reaction promoted by strong base between two polyoxaethylene units of varying length, one of which bears two terminal OH groups, and the other two leaving groups. We now report a different approach, based on the action of hydroxide ion on polyethylene-glycol dibromides BrCH2(CH2OCH2)x-1 CH2Br, with X = 5, 6, and 7, in highly concentrated water solution in the presence of Ba++ ion. The most significant feature of the present method is that it requires only one building block, bearing one less oxygen atom than the crown ether to be formed.5 The last oxygenKeywords
This publication has 6 references indexed in Scilit:
- General synthesis of substituted and unsubstituted crown ethersJournal of the Chemical Society, Chemical Communications, 1978
- Kinetic evidence for the template effect of added cations on the rate of formation of benzo-18-crown-6 in water solutionJournal of the American Chemical Society, 1977
- Principles and Synthetic Applications in Crown Ether ChemistrySynthesis, 1976
- Macroheterocycles. Oxetane function spiro to macrocyclic polyether ringsThe Journal of Organic Chemistry, 1974
- Cyclic oligo-ethers related to ethylene oxideJournal of the Chemical Society D: Chemical Communications, 1971
- Cyclic polyethers and their complexes with metal saltsJournal of the American Chemical Society, 1967