Azacrown Ethers as Amphiphile Headgroups: Formation of Stable Aggregates from Two- and Three-Armed Lariat Ethers

Abstract

Ten 18-membered ring lariat ether compounds have been prepared as one-, two-, and three-armed derivatives of aza-, diaza-, and triaza-18-crown-6. They include N-[[(3-cholestanyloxy)carbonyl]methyl]aza-18-crown-6, 1, N-tetradecylaza-18-crown-6, 2, N,N‘-dibutyl-4,13-diaza-18-crown-6, 3, N,N‘-dinonyl-4,13-diaza-18-crown-6, 4, N,N‘-didodecyl-4,13-diaza-18-crown-6, 5, N,N‘-ditetradecyl-4,13-diaza-18-crown-6, 6, N,N‘-dioctadecyl-4,13-diaza-18-crown-6, 7, N,N‘-bis[[(3-cholestanyloxy)carbonyl]methyl]-4,13-diaza-18-crown-6, 8, N,N‘-bis[[(3-cholestanyloxy)carbonyl]decyl]-4,13-diaza-18-crown-6, 9, and N,N‘,N‘‘-tri-n-hexyl-4,10,16-triaza-18-crown-6, 10. Compounds 2, 8, and 9 are previously unreported. Aqueous suspensions of these monomers were sonicated, and the first evidence for stable aggregates formed from diaza and triaza lariat ethers (3−10) was obtained. The formation of aggregates from 3 or 10 is especially notable since the side chains are butyl or hexyl, respectively. The aggregates were studied by a combin...