Synthesis and characterization of a novel calix[4]arene tetramethyl tetraether

Electrochemical Synthesis of a Tetradentate Copper N-Heterocyclic Carbene Calix[4]arene and Its Transmetalation to Palladium: Activity of the Palladium Complex in Suzuki–Miyaura Cross-Coupling

“…Tetrakis( p -methylimidazolium) mesityl calix[4]arene 3 was readily prepared by reacting tetrakis( p -bromomethylated) mesityl calix[4]arene 1 with tert -butyl acetate imidazole 2 in THF (Scheme ). Compounds 1 and 2 were prepared using literature procedures. − It was found necessary to purify the imidazole compound 2 using column chromatography (10% MeOH/chloroform, I 2 active by TLC) to remove imidazolium byproducts, otherwise they were carried through to the final metal products. Compound 3 was isolated as a white solid and fully characterized.…”

“…All reagents were used as supplied or prepared as outlined without need for further purification. Tetrakis- p -bromomethylated mesityl calix[4]arene 1 and tert -butyl acetate imidazole 2 were prepared according to literature procedure. − 1 H and 13 C NMR spectra were recorded on a Bruker DPX300 spectrometer (operating frequency 300.1 MHz for 1 H and 75.48 MHz for 13 C) or on a Bruker DRX500 spectrometer (operating frequency 500.13 MHz for 1 H and 125.03 MHz for 13 C). Chemical shift values are quoted in parts per million (ppm, δ), and coupling constants J are quoted in hertz (Hz).…”

Modular assembly of a preorganised, ditopic receptor for dicarboxylates

“…[19][20][21][22][23] The mesityl, hydrocarbon calix [4]arene 1 is readily prepared in one step from a9-chloroisodurene. 24 It is locked into a 1,3-alternate conformation of the aryl rings and has been used as a scaffold for organometallic units 25 and, as a nitrile or pyridyl derivative, as a ligand in the formation of coordination arrays. 26,27 Reaction of 1 with paraformaldehyde in the presence of Zn-HBr results in facile bromomethylation of the aryl rings to give 2 (characterised spectroscopically, by elemental analysis and X-ray crystallography).…”

Allosteric effects in a tetrapodal imidazolium-derived calix[4]arene anion receptor

“…All reagents were purchased from commercial sources and were used without further purification. Calix [4]arene 1 was prepared from a¢-chloroisodurene 32 and reacted with paraformaldehyde in the presence of Zn-HBr to give 2. 14,36 1 H, 13 C, 1 H-1 H COSY, 1 H- 13 C HSQC and 1 H- 13 C HMBC spectra were obtained from a Varian INOVA 500 spectrometer at a frequency of 500 MHz for 1 H and 125 MHz for 13 C or from a Bruker Avance 400 at a frequency of 400 MHz for 1 H and 100 MHz for 13 C. Mass spectrometry data were obtained on a Thermo Finnigan LTQ spectrometer in ES+ and EI mode.…”