Page 20 - Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005)

IR-9.3 C O O R D I N A T I O N C O M P O U N D S

H
H N N
2
N NH 2
H
0
N,N -bis(2-aminoethyl)ethane-1,2-diamine
Examples:
4. 5. 6.
3 1 1
1 1' 3 1' 3 3

2 2' 2 2' 2 2'
3 3 1'
0
0
OC-6-2 2 OC-6-32 OC-6-1 3
Pentadentate and hexadentate ligands can be treated similarly. E xamples 7 a nd 8 a pply to
stereoisomers of classic linear hexadentate ligands, w hereas Examples 9 a nd 10 apply t o
ligands containing a b ranched structure.

Examples:

7. 8.
3' 1
3 2' 2 2'

2 1' 3 3'
1 1'

OC-6-3 3 OC-6-1 3
0
0 0
9. 10.
1 1
2 1 3 1

5 4 5 4
3 2

OC-6-53 OC-6-52

Example 11 illustrates the use of priming for assigning absolute c onfiguration in a n on-
octahedral structure. The chirality designation is determined by the system of assigning
primes t o l igands with the extra requirement that the symbol 1 o n t he top face is placed
00
above the symbol 1 on the bottom face. This produces the sequence shown and the chirality
symbol C when viewing the prism from above the top face. T he stereochemical d escriptor is
00
0
TPR-6-1 11 -C. T he skew-lines method (Section I-9.3.4.11) could also be applied and would
give in this case the descriptor e.

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