
TY  - JOUR
A1  - Wei, G. 
A1  - Hambley, T. W. 
A1  - Lawrance, G. A. 
A1  - Maeder, M. 
T1  - Synthesis and Complexation of a Chiral Sexidentate Pendant-Arm Macropolycyclic Polyamino Acid
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 2002
VL  - 55
IS  - 10
SP  - 667
EP  - 673
KW  - 
UR  - https://doi.org/10.1071/CH02088 
N2  - The reaction of the acyclic complex ion (methyl (SS,SS)-3-[(2´-aminocyclohexyl)amino]-2-[(2´-aminocyclohexyl)-aminomethyl]propionate)copper(II) with formaldehyde and nitroethane in basic solution yields the pendant-arm macrocyclic complex (SS,SS)-(methyl-15-methyl-15-nitro-2,6,13,17-tetraazatricyclo[16.4.0.07,12]docosane-4-carboxylate)copper(ii) ion. Reduction with zinc in hydrochloric acid yields the hydrochloride salt of the pendant-arm macrocycle (SS,SS)-15-amino-15-methyl-2,6,13,17-tetraazatricyclo[16.4.0.07,12]docosane-4-carboxylic acid (1), separated into and isolated as the major trans (1a) and minor cis (1b) isomers. Co-ordination of (1) to several metal ions [CoIII, CrIII, NiII, ZnII, CuII] and comparison with a previously reported analogue without the cyclohexane rings, trans-13-amino-13-methyl-1,4,8,11-tetraazacyclotetradecane-6-carboxylic acid (2a) salt, is described. The [Ni{(1a) &#8211; H+}](ClO4) crystallizes in the monoclinic space group P21, a 9.710(2), b 14.442(1), c 10.317(2) &#197;, &#946; 96.02(2)&#176;. The nickel displays a distorted octahedral geometry, with all four secondary amines coordinated (Ni&#8211;N range 2.044(7)&#8211;2.063(6) &#197;), in addition to pendant primary amine (Ni&#8211;N, 2.109(6) &#197;) and carboxylate (Ni&#8211;O, 2.100(6) &#197;) groups. Protonation constants for the trans (1a) and cis (1b) isomers and stability constants of these isomers with the labile metal ions ZnII, CdII, HgII, PbII, MnII, and CoII were determined by potentiometric titrations. The log K values for 1 : 1 complexes show small variations between geometric isomers. 
ER  -

