88454-94-8Relevant articles and documents
Synthesis of New Optically Active Crown Ethers
Dehmlow, Eckehard V.,Knufinke, Volker
, p. 1091 - 1094 (2007/10/02)
Optically active crown ethers 1a-11, 2, 3a,b, 4a,b, 5a,b and the analogue 6 are synthesized.The efficiency of these compounds as phase-transfer catalysts for a series of enantioselective reactions will be tested.This will be described in a following publication. Key Words: Crown ethers, chiral, optically active / Phase transfer catalysts
Synthesis of Lipophilic 18-Crown-6 Diacids for the Membrane Transport of Alkaline-Earth Cations
Fyles, Thomas M.,McGavin, Cynthia A.,Whitfield, Dennis M.
, p. 753 - 761 (2007/10/02)
The synthesis of three different types of lipophilic 18-crown-6 diacids is described.A didecyl crown ether 2,3-diacid (1) was prepared as a minor product from a diiodide precursor (12) and threo-11,12-docosanediol by thallous ethoxide cyclization.The major nonpolymeric products resulted from elimination followed by cyclization to give 15-crown-5-derivatives.A crown ether 11,12-diamide 2,3-diacid (4) was prepared by a similar route involving cyclization of a benzyl protected precursor (26) and N,N,N',N'-tetramethyltartaramide (9).Isomeric syn and anti 2,11(12)-diamide 3,12(11)-diacid derivatives 6 and 7 were prepared from the known crown ether bisanhydride 8 and alkylamines.The product mixture was separated by chromatography, and the isomers were identified by comparison of acidity and stability constants for complexation with those of closely related syn/anti crown ether acids.