Methoxy-ether and crown-ether ­derivatives of tetrahomodioxa- and octahomotetraoxacalix­[4]­arenes

Three methoxy­-ether and one methoxy-­ether/crown-ether derivatives of p-tert-butyl­tetrahomodioxa- and p-R-octahomo­tetraoxacalix­[4]­arenes (R = methyl, tert-butyl, H) have been investigated. The first three compounds, 7,15,21,27-tetra-tert-butyl-29,30,31,32-tetra­methoxy-3,11-dioxapenta­cyclo­[23.3.­1.1^5,9.1^13,17.1^19,23]­ditriaconta-1(29),5,7,­9(30),­13,15,-17(31),­19,21,23(32),25,27-dodecaene, C₅₀H₆₈O₆, 33,34,35,36-tetra­methoxy-7,15,23,31-tetra­methyl-3,11,19,27-tetra­oxa­penta­cyclo[27.3.1.1^5,9.1^13,17.1^21,25]­hexa­tri­aconta-1(33),5,7,9(34),13,15,­17(35),21,23,25(36),29,31-dodecaene, C₄₀H₄₈O₈, and 7,23-di-tert-butyl-33,34,35,36-tetra­methoxy-3,11,19,27-tetraoxapenta­cyclo­[27.3.1.1^5,9.1^13,17.1^21,25]­hexatriaconta-1(33),5,7,9(34),13,15,­17(35),- 21,23,25(36),29,31-dodecaene, C₄₄H₅₆O₈, in the partial-cone or 1,2-alternate conformations, present the common feature of methoxy-­ether self-inclusion, while the fourth, 42,43-di­methoxy-7,15,23,31-tetra­methyl-3,11,19,27,34,37,40-heptaoxahexa­cyclo[15.15.9.1^5,9.1^21,25.0^13,41.0^29,33]­tritetra­conta-5(42),6,8,13(41),­14,16,21(43),22,24,29(33),30,32-dodecaene, C₄₂H₅₀O₉, adopts the 1,3-alternate conformation owing to the presence of a 1,3-polyether chain.