Ian Fleming was an undergraduate (1956-1959), graduate student (1959-1962), a Research Fellow and Fellow, in Pembroke College, Cambridge, obtaining his PhD supervised by the late Dr John Harley-Mason. Except for a postdoctoral year (1963-1964) at Harvard with Professor R. B. Woodward, and sabbatical visits to McGill University in Montreal (1972 & 1978), the University of Wisconsin in Madison (1980), and Harvard University (1990), he has spent his entire academic career in Cambridge, where he was successively a University Demonstrator, an Assistant Director of Research, a University Lecturer, a Reader in Organic Chemistry, and Professor of Organic Chemistry. He is now an Emeritus Professor of Chemistry in Cambridge.

He began his research career with a wide range of synthetic and mechanistic studies in organic chemistry, with contributions to synthetic methodology, mechanistic understanding, photochemistry, and mass spectrometry. Most strikingly, he participated in Woodward’s total synthesis of vitamin B12 by carrying out in 1964 one of the key steps setting up two contiguous stereogenic centres on the western side, and in 1966, he settled the final detail in the structure of chlorophyll—the absolute configuration of the stereogenic centres in the macrocyclic ring.

He is best known for his work since 1972 on organosilicon chemistry applied to organic synthesis. He early appreciated that its weak metallic properties were suited to solving several problems of regioselectivity and control in organic synthesis. He coined the idea of the trimethylsilyl group as a “super” proton, making it clearer how organic chemists should think about the ways in which silicon might be useful. He showed that a silyl-cuprate reagent reacts with a variety of functionalised molecules, and that the phenyldimethylsilyl group introduced in this way influences the chemistry, and especially the stereochemistry of events in its neighbourhood in a completely different way from a hydroxy group, but can be converted into a hydroxy group, with retention of configuration, when desired. In particular, he demonstrated how it induces high levels of open-chain stereocontrol in the synthesis of ten small molecules: loganin, dihydronepetalactone, the Prelog-Djerassi lactone, thienamycin, a carbacyclin analogue, tetrahydrolipstatin, a prostaglandin intermediate, lavandulol, deoxyribonolactone and nonactin.

He has also been influential as a teacher of undergraduates, and as a Director of Studies in Chemistry; 71 of his graduate students have obtained PhDs; and 94 other students and post-doctoral co-workers have been members of his research group at one time or another. He has written several reviews, edited two major reference works, and is the author of five textbooks: Spectroscopic Methods in Organic Chemistry and Spectroscopic Problems in Organic Chemistry (McGraw Hill), both with Dudley Williams, Selected Organic Syntheses (Wiley, 1972), Frontier Orbitals and Organic Chemical Reactions (Wiley, 1976), and Pericyclic Reactions (OUP, 1999). He has just finished a substantial work Molecular Orbitals and Organic Chemical Reactions enlarging upon and bringing the Frontier Orbitals book up to date.

He was awarded the Tilden lectureship of the Royal Society of Chemistry in 1981 and their Prize for Organic Synthesis in 1983, and in 1993 he was elected a Fellow of the Royal Society.