ChemInform Abstract: SYNTHESIS AND X‐RAY CRYSTAL AND MOLECULAR STRUCTURE OF A NOVEL MACROBICYCLIC LIGAND: CROWNED P‐TERT‐BUTYLCALIX(4)ARENE

Abstract

Durch Umsetzung des p‐tert.‐Butylcalix[4]arens (I) mit dem Ditosylat (II) erhält man den bicyclischen Kronenether (III).

The Lithiation/Oxygenation Approach to Calix[6]arenes Selectively Functionalized at a Pair of Opposite Methylene Bridges

“…This process involves “flipping” of the two opposite rings, which are nonadjacent to the functionalized bridges (in blue in Figure ). In the 1,2,3-alternate conformation, the axial methylene protons (“a”) should resonate at a lower field than the equatorial ones (“e”), as usually observed in calixarenes, due to the proximity of the former to the ether oxygens. Pairs of geminal isoclinal protons (located on a methylene bridges connecting a ring pointing “up” with a ring pointing “down”) are diastereotopic (denoted i and i′ in Figure ).…”

New syntheses of calixarene-p-sulphonates and p-nitrocalixarenes

“…Calix [8]arene-p-octasulphonic Acid (2; n = 8).-This compound was prepared from (1; n = 8) according to the method similar to that of (2; n = 4), (yield 8873, m.p. > 300 "C; 6(D20) 4.11 (16 H, s, ArCH,Ar) and 7.61 (16 H, s, ArH); v,,,.…”

“…for C,,H,,0,2S,Nal,~18H,0: C, 32.1; H, 3.4%). [8]arene (3; n = 8) by Method A.-65% HNO, (2.2 g) was added dropwise at 0-5 "C to compound (2; n = 8) (2.0 g, 1.2 mmol) dissolved in 52% H2S04 (71.3 g) at 0 "C and the solution was stirred below 10 "C for 10 h. Dilution of the reaction mixture with water gave a finely dispersed precipitate which since it could not be recovered by the conventional filtration was isolated by centrifugation and washed with water. It was then dissolved in alkaline solution and treated with active charcoal.…”

“…for C56H40N,0,4*12H,0: c , 47.2; H, 4.5; N, 7.9%). p-Nitrocalix [8]arene (3; n = 8) by Method B.-Compound (1; n = 8) (2.0 g, 2.3 mmol) was dissolved in concentrated H2S04 (40 ml) and the solution heated at 80 "C for 4 h. After cooling, the reaction mixture was diluted with cold water (67 ml) (the H2S04 concentration is 37% at this stage) and then treated with 65% HNO, (4.8 g) at 5-10 "C for 10 h. The purification method is similar to that of method A [yield from…”

Constructing a Nonfluorescent Conformation of AIEgen: A Tetraphenylethene Embedded in the Calix[4]arene's Skeleton

“…Generally, calix[4]arenes in which one or more of the OH groups on the bottom rim are converted to OMe groups also exist in the cone conformation, for example, the monomethyl ether, the dimethyl ether, the trimethyl ether, and the tetramethyl ether of p ‐ tert ‐butylcalix[4]arene. The hydroxyl groups of the Calix‐DPE(OH) 4 were methylated with MeI.…”