one proton at each of the two proton-donating atoms separated by one covalent bond, it was shown that uncharged crystalline supramolecular compounds can be obtained on account of the proton-donating characteristics of the aromatic heterocycles.An indispensable condition for the formation of crystalline supramolecular compounds [1, 2] of crown ethers with organic molecules is the presence in the latter of proton-donating centers with one of the atoms C, N, or O, particularly H 2 N-, H 2 NSO 2 -, H 2 NCS-, H 2 NHNCO-, H 2 C=, H 3 C-, H 3 CO-, and similar groups or water molecules [1-3], securing stabilization of the components of the supramolecular compound by hydrogen bonds. As a rule a pair of protons of the substituent takes part in bonding, and the stability of the compounds decreases in the following order: OH > NH 2 > CH 2 [4]. The crystalline supramolecular compounds of crown ethers with heterocycles are stabilized by hydrogen bonds either through one of the above-mentioned substituents in the heterocycle [5][6][7][8][9][10][11][12] or the cyclic ammonium group of the protonated heterocycle [13]. A single example of the formation of a crystalline supramolecular compound of the most effective [3,14] crown ether 1b with unsubstituted triazole is known [15].The aim of this work was to determine the possibility of synthesizing uncharged crystalline supramolecular compounds of various crown ethers with five-membered aromatic heterocycles, containing one proton at each of two adjacent proton-donating atoms separated by one covalent bond and securing stabilization of the supramolecular compound by analogy with the data in [15].It was established that the crystalline supramolecular compounds [1b·4]-7, [2·4]-8, [3·2(4)]-9, [1a·5]-10, [1b·2(5)]-11, [2·2(5)]-12, [3·2(5)]-13, and [3·2(6)]-14 respectively are formed during spontaneous evaporation of the solvents from solutions of the crown ethers 1-3 with the respective heterocycles 4-6.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.