Trefoil helical dinuclear complex

We realized that improvement in the yields of trefoil knots would be determined by (i) the proportion of double helix precursor formed compared with face-to-face open chain complex (Figure 18) (ii) the spatial arrangement of the four reacting ends of the helical dinuclear complex. This latter factor will reflect the extent of winding of the two molecular strings interlaced around the copper atoms. The various complexes synthesized and studied are depicted in Figure 21 [96]. 

Fig. 9. The dinuclear double-stranded helical complex [Cu2(L,3)2](BF4)2 is utilized as the precursor of the trefoil knot system. (From Scheme 1 in Dietrich-Buchecher, C. D. Sauvage, J.-P. Cian, A. D. Fischer, J. J. Chem. Soc., Chem. Commun. 1994, 2231.)...

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