1.2- Ethanediamine complexes

The isolation of imine complexes formed by the condensation of acetaldehyde with Co -1,2-ethanediamine complexes has also been described. In one case two such acetaldimine moieties condense stereospecifically. Another acetaldimine product derived from A-[Co(en)2(5-Tyr)] was also prepared and its crystal structure determined. 

Syntheses reported for the pentaammine(trifluoromethanesulfonato-O) complexes can be readily adapted for other amine or multidentate amine analogs. Syntheses of coIbalt(III) complexes with 1,2-ethanediamine or A -ethyl-l,2-eth-anediamine ligands have been reported earlier in this series. To exemplify the procedures further, trifluoromethanesulfonato-O complexes of cobalt(III), chro-mium(III), and rhodium(III) with unidentate methylamine ligands based on the readily prepared [M(NH3)5Cl]Cl2 precursors are reported here. The following sections report syntheses of 1,2-ethanediamine complexes of Rh(III) and Irflll) and of Ru(II) and Os(II) diimines with trifluoromethanesulfonato ligands. Such syntheses indicate the diversity of the synthesis technique, and the complexes described are excellent precursors for other compounds. 

Introduction of chiral centers in the nonleaving groups can achieve interesting binding differences for enantiomers toward DNA. For example, [PtCR-DACH)Cl2] binds to DNA twice as strong as the S-enantiomer (143). Pt(II) complexes containing the meso form of 1,2-bis(2-hydroxyphenyl) ethanediamine exhibit the lowest antitumor activity and reactivity because of the steric hindrance provided by the aromatic rings (144). 

Lithium acetylide-ethylenediamine complex Ethylenediamine, compd. with lithium acetylide (Li(HC2)) (1 1) (8) 1,2-Ethanediamine, compd. with lithium acetylide (Li(HC2)) (1 1) (9) (6867-30-7)... 

Kx for copper (II)-diamine complex is 10.36 and 9.45 for 1,2-ethanediamine and 1,3-propanediamine, respectively (-2)]. The large difference in the stabilities of the two copper (II)-diamine complexes is attributed to an unfavorable entropy effect associated with an increase in the size of the metal-chelate ring (2). Extrapolating to the / -ketoimine derivatives, it seems reasonable to expect that the stability of bisacetylacetonetrimethylenediiminocopper(II) would be less than that of the ethylenediamine analog and to suspect that the former compound is less stable than bis-(4-iminopentane-2-ono) copper (II). That this is reasonable is... 

C H402, Acetic acid palladium complex, 26 208 tungsten complex, 26 224 C2H7PS, Phosphine sulfide, dimethyl-manganese complex, 26 162 C H,N2, 1,2-Ethanediamine chromium complex, resolution of, 26 24, 27... 

NjChHh, 1,2-Ethanediamine, N,N,N, N -tetramethyl-lithium complex, 26 148 NjCmH, 2,2 -Bypyridine rhenium complexes, 26 82, 83 N2C, H, Azobenzene cobalt and palladium complexes, 26 175, 176... 

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