10.1039/b714735j
The study presents new synthetic conditions for the selective formation of the rctt chair stereoisomers of octa-O-alkyl resorcin[4]arenes, which are significant in supramolecular chemistry due to their symmetrical 'bowl' shape cavities that can function in molecular recognition and sensing. The synthesis involves the condensation of 1,3-dimethoxybenzene with various aldehydes, including straight-chain, branched-chain, aromatic, and masked aldehydes, under Br?nsted acid catalysis in acetic acid solutions. The purpose of these chemicals is to create specific resorcin[4]arene derivatives that can complex a range of cations and neutral electron-acceptors, with potential applications in chiral recognition and the development of complex structures through selective functionalization. The study also investigates the thermodynamic stability of the rctt chair stereoisomer over the rccc boat stereoisomer, a finding supported by molecular modeling and quantum chemical calculation studies.
10.1016/S0040-4020(01)90320-5
The research focuses on novel secondary Friedel-Crafts acylation reactions of certain arenes, including dimethyl resorcinol, m-xylene, m-methylanisole, and m-chlorotoluene, using dichloroacetylchloride and anhydrous AlCl3 as catalysts. The purpose of the study was to explore the formation of unexpected products, which was found to depend on the nucleophilicity of the arene and the electrophilicity of the acyl carbonyl of the initially formed acylated product. The research concluded that higher molar proportions of the arene and sometimes elevated temperatures are necessary for the generation of these products, and the reaction pathway is influenced by the formation of possible complexes of AlCl3 and dichloroacetylchloride with groups adjacent to the dichloroacetyl function, especially at higher temperatures. The study demonstrated the potential of this method for preparing novel polyaryl compounds using substrates of varied nucleophilicity at different reaction temperatures.
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