UCRL 1 337

ABSTRACT OF PAPER PRESENTED AT THE SYMPOSIUM ON 1ETAL CHELATE CHEMISTRY
AT BROOKLYN POLYTECHNIC INSTITUTE ON APRIL 26, 1952
BY MELVIN QdLVIN
The essential structural element which differentiates metal chelate compounds
from metal coordination compounds, or metal complexes in general, is the e::istence of
some linkage between two or more of the donor atoms in the first coordination sphere
of the metal. It is the purpose of the present discussion to examine the influenc-i
that this structural factor may have upon the physical and chemical properties of
chelate compounds. Examples of well known, simple coordination compounds involving
variety of donor atoms (Oxygen, Nitrogen), as well as a variety of electrostatic sir,
ations, are shown in the following formula. Below each one are listed a few corres-
ponding chelate structures,
NH                     -     NH    (-1) +2              NH
H3N    (3    NH3            H3N    I 3  OH              HqN   , 3    OH2
+3                         Co3                       C3
Co                                                      C
H N"'I       NH              H3N    I    NH             HEN      \   NH
NH3    3                   NH iNH3                            3
-3        -               -3          -
(= )

NH2- CH
Co 2
\NH2-C
H
0-C
H

NH-    CH                    0 -C
2                             -  -
2
H2                     O     \H
Co~ _
co
H
Various types of complex Ions and chel ute compounds

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