ANNUAL REPORT - Australian Academy of Science

Alan McLeod Sargeson
Died 29 December 2008, elected to Fellowship 1976.
Alan Sargeson was born in Armidale, NSW, on 13 October
1930 to Herbert Leslie Sargeson, a magistrate, and Alice
McLeod Sargeson. He had two older brothers both now
deceased. Because of his father’s occupation he moved
frequently and consequently often changed schools.
Despite these frequent disruptions, Alan enjoyed his
school years developing an early interest in science.
Expecting to become a school teacher he studied
science at the University of Sydney where he received
an honours degree in organic chemistry (1952). He,
however, was more attracted to inorganic coordination
chemistry because of his acquaintance with Frank Dwyer,
a coordination chemist of considerable distinction. With
Dwyer he completed his doctorate titled The Metal-oxygen Bond in Inorganic Complexes in 1956. In the same
year, rather than pursuing a school teaching career, he took a lectureship in the University of Adelaide. While
in Adelaide he met his wife Marietta whom he married in 1959. They had four children, Kersten, Frank, William,
and Bente. All survive him.
The possibility of Dwyer leaving Australia prompted the John Curtin School of Medical Research at the ANU
to set up a research unit for him to pursue work in a field he had initiated, bioinorganic chemistry. Alan was
asked to join the group in Canberra. In 1958 he moved there as a research fellow. During the next four years
he first collaborated with Dwyer on the antibacterial activity of o-phenanthroline and 2,2’-bipyridyl metal
complexes and on the diasterioselectivity found in dissymmetric octahedral complexes containing chiral
ligands. The latter was a long-standing problem that had defied solution until the work of Sargeson and
Dwyer.
After this initial collaboration, he began his own independent career at the medical school where he initiated
seminal studies on the chirality and configurational stability of metal coordinated amine ligands. This elegant
and arresting work proved to be pivotal for understanding the factors controlling the topology of complexes
derived from multidentate ligands. The medical school thrived until 1962 when Dwyer died suddenly leaving
Alan with the responsibility of leading the unit. He ably ran the unit until the establishment of the Research
School of Chemistry to which he transferred in 1967 as a senior fellow.
He completed his career at the school despite receiving attractive offers from other institutions. He soon
became a Professorial Fellow (1968) and was elevated to the rank of professor in 1978. Although he did not
relish the prospect of becoming dean of the school, he accepted the position (1986–1988) out of a sense of
duty and responsibility to his colleagues. He retired in 1996 to become Professor Emeritus. He frequented the
department often until his death.
OBITUARY NOTICES
Alan worked with many talented students, postdoctoral fellows and senior collaborators but his ideas and
scientific judgment anchored and propelled the work. Early on Alan hired David Buckingham, a former
Dwyer student, to join him as senior member of the group. The collaboration that ensued proved remarkably
productive and synergistic. Their respective strengths were complementary. The collaboration produced
several important discoveries. Perhaps the most notable of these was the demonstration that stable cobalt
complexes could be used to hydrolyse amino acid esters and peptide bonds by rates one million time faster
than those observed in dilute solution. This work demonstrated with remarkable clarity the origins of the
rate accelerations observed in similar enzyme reactions. Another important piece of work that emerged
from this collaboration was the demonstration that base hydrolysis of cobalt amine complexes occurred by
a base catalysed mechanism. This work showed Alan’s incisiveness and cleverness in elucidating reaction
mechanisms. Eventually Buckingham left the school to return to New Zealand as a professor.
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THE AUSTRALIAN ACADEMY OF SCIENCE