He was then appointed Assistant Lecturer at
Birkbeck College, London in 1955 (moving in at the bottom as Professor
Derek Barton moved out at the top to take up the Regius Chair in
Glasgow). After two years at Birkbeck, Rees moved to
King's College London where he spent eight years as Lecturer/Reader. He collaborated for several years with Professor
Donald Holroyde Hey on various aspects of
heterocyclic chemistry. He was appointed to his first Chair at the
University of Leicester in 1965, and four years later moved to the
University of Liverpool as Professor of Organic Chemistry, and in 1977 he succeeded Professor
George Wallace Kenner there as Heath Harrison Professor of Organic Chemistry. In 1978, he was appointed
Hofmann Professor of Organic Chemistry at
Imperial College London and remained there until his retirement in 1993. Rees' research interests ranged widely over mechanistic and synthetic organic chemistry. Much of his work was concerned with
heterocyclic chemistry, particularly the synthesis and chemistry of new
heterocyclic rings, with an emphasis on
aromatic and
antiaromatic rings, and the role of
reactive intermediates in heterocyclic chemistry. Recently, he had been working on heterocyclic systems with unusually high proportions of
nitrogen and
sulphur heteroatoms. He published about 480 papers in the scientific literature. Rees was the President of the
Royal Society of Chemistry from July 1992 for two years. He has served on its Council and many Boards and Committees at various times; he was Chair of the Publication and Information Board for four years. He was President of the Perkin Division of the RSC, and President of the Chemistry Association for the Advancement of Science. Amongst the many and diverse contributions to chemistry he made, his two papers describing the brilliantly conceived generation of
benzyne and by the
lead(IV) acetate oxidation of N-amino heterocycles are considered classic papers from this era. He died on 21 September 2006 of undisclosed causes. ==Awards and honours==