Stereoselective Synthesis and Structure of New Types of Calix[4]resorcinarenes. Complexation of Tetrakis(O,O-Phosphorus)Bridged-Calix[4]resorcinarenes with Heavy Metal Atoms
✍ Scribed by Peyman Sakhaii; Ion Neda; Matthias Freytag; Holger Thönnessen; Peter G. Jones; Reinhard Schmutzler
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- German
- Weight
- 243 KB
- Volume
- 626
- Category
- Article
- ISSN
- 0372-7874
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✦ Synopsis
The acid-catalyzed (with HCl) condensation reactions of resorcinol ( ) with 1-naphthaldehyde (2) and isobutyraldehyde (3) furnished the tetrameric macrocyclic compounds 4 and 6. Detailed NMR-investigations of the acetylated tetrameric species 5 surprisingly support a structure not in agreement with the expected all-cis conformation. The chair conformation (C 2h symmetry) of the acetylated derivative 5 was established through a crystal X-ray diffraction study. The naphthyl substituents are arranged in trans position above and below the plane made up by the resorcinol units. The reaction of resorcinol 1 with isobutyraldehyde, in accord with expectation, led to the calix[4]resorcinaren (6). The 1 H NMR spectra of compound 6 and 7 appeared at room temperature as broad signals, indicating a conformation of C 2v symmetry. The reaction of the C-methyl-tetrakis-P-(chlorodioxaphosphocin)-calix[4]resorcinarenes ( ) and ( ) with suitable N-trimethylsilyl organic amines were conducted in tetrahydrofuran suspension, fur-nishing the P±N-substituted calix[4]resorcinarenes ( ) and ( ). While in the complexation of C-methyl-tetrabromotetrakis-P-(dimethylaminodioxaphosphocin)-calix[4]resorcinarene ( ) with (tht)AuCl (tht = tetrahydrothiophene) the expected, neutral tetra-substituted complex 15 was formed, the reaction of 13 with moist acetonitrile led to the anionic atomic framework 14. X-ray structure determinations of the complexes 14 and 15 show that both possess the cone conformation. In the gold complex 15, the Au±Cl groups form a loose aggregate, with three Au ´´´Cl contacts of 316±340 pm; one of the groups points towards the centre of the cone. The copper(I) complex 14 displays crystallographic mirror symmetry, with a central Cu 4 Cl 5 unit involving tetrahedrally coordinated copper.