NEW CYCLAM-TYPE COPPER(II) COMPLEXES WITH AMIDE MOLECULAR PADLOCK - SYNTHESIS, PROPERTIES AND CRYSTAL-STRUCTURE

The macrocyclic complex CuL1(ClO4)(2) (L-1: 1-formyl-1,3,6,10,1 3-pent aazacyclotetradecane ) has been prepared. Two isomeric forms of CuL1(C lO4)(2) were obtained. The structures of these isomers were determined by X-ray diffraction analysis. The structure of the closest homologue , CuL2(ClO4)(2). MeCN (L-2: 1-acetyl-1,3,6,10,13-pentaazacyclotetrad), was determined for comparison. Macrocyclization was also successful u sing Cu(en)(2)(2+) as the starting compound. The decrease of the locki ng fragment size in 1-formyl-1,3,6, 10,13-pentaazacyclotetradecane com plexes changes the counterion coordination to the macrocyclic cation. No direct interaction between the locking nitrogen atom and the centra l metal ion was detected. The syntheses of CuL3(ClO4)(2)(L-3: ,8-difor myl-1,3,6,8,10,13-hexaazacyclotetradecane) and CuL4(ClO4)(2) (L-4: 1-( hydroxypropionyl) -1,3,6, 10,13-pentaazacyclotetradecane) are also rep orted. (C) 1998 Elsevier Science S.A. All rights reserved.