Synthesis and structures of O-anthrylmethyl-substituted hexahomotrioxacalix[3]arenes

Abstract

3]arene (1H 3 ) with 9-chloromethylanthracene 5 was carried out under different reaction conditions. Variation of the number of anthrylmethyl group introduced at the phenolic rim of hexahomotrioxacalix[3]arene 1H 3 was achieved through selective O-alkylation using stoichiometric amounts of 9-chloromethylanthracene 5 in acetone to afford the mono-O-alkylated product 2H 2 An, the di-O-alkylated product 3HAn 2 and the tri-O-alkylated product partial-cone-4An 3 , respectively. Interestingly, by using an acetone/benzene (1:1 v/v) mixed solvent system, the cone-4An 3 was successfully synthesized. These results suggest that the solvent can also control the conformation of the O-alkylation products. The possible reaction routes of the cone-4An 3 and partial-cone-4An 3 are also discussed.

Synthesis of Mono-O-alkylated Homooxacalix[3]arene and a Protection–Deprotection Strategy for Homooxacalix[3]arene

“…Interestingly, recently studies conducted in our laboratory have demonstrated that the di-O-9-anthrylmethyl-substituted homooxacalix[3]arene 2HAn2 was conveniently synthesized in good yield by the reaction of 1H3 with 9-anthrylmethyl bromide. 12 This finding inspired us to further explore the possibility of utilizing 9-anthrylmethyl group as a protecting group for homooxacalix[3]arene. Thus, we have attempted to synthesize the mono-O-alkylated homooxacalix[3]arene 4PrH2 by using 9-anthrylmethyl as protecting groups, and the synthetic route is shown in Scheme 3.…”

“…Interestingly, recent studies conducted in our laboratory have demonstrated that the di- O -9-anthrylmethyl-substituted homo­oxacalix­[3]­arene 2HAn 2 could be conveniently synthesized in good yield by the reaction of 1H 3 with 9-anthrylmethyl bromide . This finding inspired us to further explore the possibility of utilizing the 9-anthrylmethyl group as a protecting group for homo­oxacalix­[3]­arene.…”