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SYNTHESIS OF THE CAGE-PENTA-AZAMACROBICYCLOALKANE 12,17-DIMETHYL-1,5,9,12,17-PENTA-AZABICYCLONONADECANE, ITS BASICITY, AND METAL COMPLEX FORMATION. CRYSTAL STRUCTURE OF THE COPPER(II) PERCHLORATE COMPLEX

DOI: 10.1039/DT9860000505

Source and publish data:

Journal of the Chemical Society, Dalton Transactions p. 505 - 510 (1986)

Update date:2022-08-04

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Authors:

Ciampolini, MarioCiampolini, Mario

Micheloni, MauroMicheloni, Mauro

Vizza, FrancescoVizza, Francesco

Zanobini, FabrizioZanobini, Fabrizio

Chimichi, StefanoChimichi, Stefano

Dapporto, PaoloDapporto, Paolo

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Article abstract of DOI:10.1039/DT9860000505

The synthesis and characterisation of the new penta-azamacrobicycloalkane 12,17-dimethyl-1,5,9,12,17-penta-azabicyclo<7.5.5>nonadecane(L) are described.Its basicity in aqueous solution has been investigated by potentiometric and spectroscopic (1H, 13C n.m.r.) techniques.The macrocycle L can take up three protons.It behaves as a very strong base (proton sponge) in the first protonation step, as a moderate base in the second step (log K2 = 8.41), and as very weak base in the last step (log K3 + in CD3CN shows a broad signal attributable to two deshielded NH protons, which are rapidly exchanged with acidic hydrogens on the n.m.r. time-scale. pH-13C N.m.r. studies have been carried out and a tentative structure for HL+, in accord with the n.m.r. features, is proposed.A number of metal ions were tested for complex formation with L.According to 13C n.m.r. spectroscopy, there was no evidence of metal co-ordination with Na+, K+, Be2+, and Al3+, whereas some weak interaction occurs for Mg2+.A lithium complex is formed at high pH.With the other metal ions, solid complexes were isolated from the reaction of the appropiate metal perchlorate and Br in boiling methanol.The molecular structure of the complex 2*H2O has been determined by single-crystal X-ray analysis.The compound crystallises in an orthorhombic unit cell (space group P21,21,21) with lattice constats a = 17.332(5), b = 15.448(5), c = 9.066(4) Angstroem, with Z = 4.Least-squares refinement converged at R = 0.058 for 1 865 observed reflections.The copper ion is wholly enclosed by the macrobicycle and is five-co-ordinatinated.The co-ordination geometry is a distored square pyramid with the secondary nitrogen atom in the apical position.The electronic spectra of the copper, cobalt, and nickel complexes show essentially the same features in the solid state and in solution, and are diagnostic of a distored square-pyramiidal structure.

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Product name:12,17-dimethyl-5-tosyl-1,5,9,12,17-penta-azabicyclo-<7.5.5>nonadecane

Cas No:103628-25-7

103628-25-7

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