Non-covalent synthesis of calix[4]arene-capped porphyrins in polar solvents via ionic interactions

R. Fiammengo, P. Timmerman, Jurriaan Huskens, Kees Versluis, Albert J.R. Heck, David Reinhoudt

Research output: Contribution to journalArticleAcademicpeer-review

34 Citations (Scopus)

Abstract

Non-covalent synthesis of calix[4]arene capped porphyrins can be achieved in polar solvents (up to 45% molar fraction of water) via ionic interaction. Thus tetracationic meso-tetrakis(N-alkylpyridinium-3-yl) porphyrins 1a–d and tetra anionic 25,26,27,28-tetrakis(2-ethoxyethoxy)-calix[4]arene tetrasulfonate 2 self-assemble in an entropy driven process in 1:1 stoichiometry with association constants K1·2 as high as 107 M−1 in methanol. The thermodynamic stability remains high even in the presence of competing salts: 10−2 M Bu4NClO4 (4500 times the concentration of the building blocks) gives a reduction in K1·2 of only 10 times. Ternary complexes 1a·2·L using 1-methylimidazole or pyridine as axial ligands (L) have been obtained with L residing outside the assembly cavity.
Original languageUndefined
Pages (from-to)757-764
JournalTetrahedron
Volume58
Issue number4
DOIs
Publication statusPublished - 2002

Keywords

  • METIS-206199
  • IR-37940

Cite this