Аннотация:The complexation of Ca(SCN)2 or Ca(ClO4)2 by a series of physiol. active P-contg. benzocrown ethers or their O analogs was studied in MeCN by IR spectroscopy and soln. calorimetry. Complex compns. at equil. were calcd. by assuming the model CaXnLm (X = anion, L = ligand, n = 0-2, m = 0-4). The IR spectra indicate that Ca coordinates to the P:O group and to some ether O atoms. Formation consts. and heats and entropies of complexation were calcd. The IR spectra indicate conformational restructuring of the coordinated ligands. The formation consts. are higher for P-contg. benzocrown ligand Ca complexes than for model ligand (MeO)2P(O)Me or (PhO)2P(O)Me complexes, but lower than for benzocrown ether complexes. The P-contg. ligands form both 1:1 and 1:2 Ca:ligand complexes. The anions (SCN-,CLO4-) affect the compns. and the stoichiometries of these complexes in soln.