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The period from 1929 to 1931 was an interesting time to be in Germany. It began with the winding up of the Allied occupation - I remember celebrating the departure of the French from Mainz with my student friends - and ended with a financial crisis involving, in Frankfurt at least, a run on the banks. During these two years, even I was aware that the Republic was crumbling, and there was widespread and growing economic distress. It seemed that government neither could nor would do anything and, hand in hand with growing disillusion and cynicism about parliamentary democracy, the extreme parties - National Socialists and Communists - began rapidly to make ground. After a good deal of violence on the streets, the Nazis gained the upper hand, the middle ground of politics fell away, and most of the public, including the student body, gradually moved over to them. This was not because they had any real sympathy for the extreme anti-Semitism of the Nazis; anti-Semitism in a mild form was, and I imagine always had been, widespread in Frankfurt but, alas, none of the men I knew really took the Nazi fulminations seriously. What the happenings during those years taught me was that economic troubles coupled with weak and vacillating government leave the way to totalitarianism wide open; all that is needed to complete the disaster is the appearance of a brilliant demagogue such as Adolf Hitler undoubtedly was. And it could happen in any country.

When I went to Germany I had no clear ideas about a career except that I wanted to do research in the natural product field, but soon it was time to think about what to do after completing the doctorate. Clearly I wanted to go back to Britain sometime but not necessarily at once. Bertie Blount was of similar mind and we did make an abortive attempt to go to Moscow to work for a spell with Zelinsky; it was probably well for both of us that it failed, for by all accounts life was pretty hard for students in the Soviet Union at that time. Blount had also been pressing me to go to Oxford with him and, since in 1930 Robert Robinson had succeeded W. H. Perkin Jr there, I decided to do so provided I could find the necessary financial support. During my short period in Glasgow in the spring of 1931 (when I did a little work on hesperidin) at the suggestion of Professor T. S. Patterson I applied for an 1851 Exhibition Senior Studentship. Entries for this had to go through one's own university, which then nominated its chosen candidates to go forward for the main competition. I remember well a somewhat discouraging interview with the Registrar of Glasgow University who said he would forward my application but that nothing would come of it since Glasgow hadn't figured in the award list for many years, and, moreover, there was an applicant in another subject who was much senior to me and would be the university's first choice. However, somewhat to my surprise, I was in fact awarded a Senior Studentship and I thereupon made arrangements to join Oriel College and start research with Robert Robinson in September 1931 on the synthesis of anthocyanins (the red and blue colouring matters of flowers). Although by that time I already held the German Dr. phil. nat., it eased the problem of entering a college if one read for a degree; since the D.Phil. course at Oxford had only a research requirement and was unlikely to influence adversely any work I intended to do, I enrolled accordingly and, indeed, took the degree in 1933.

When I went to Oxford people in my position, i.e. graduates from other universities coming to do advanced work, often found great difficulty in fitting fully into college life, and not a few of those who were my contemporaries never really became part of the colleges which they joined. In Oriel I was much more fortunate, became thoroughly integrated and, indeed, came to be regarded as an 'Oriel man' just as much as those who had come up as undergraduates. This made a great difference to my social life in Oxford and, since, after taking the D.Phil. in 1933, I was made a member of the Oriel Senior Common Room I really saw a lot of college life both of the student and the don. It is perhaps only fair to say that my ready integration into Oriel really rested on sporting ability. When a newcomer came to the college the various clubs used to descend upon him to see if he had any qualities that would be useful to them. Now, it happened that I had played quite a lot of lawn tennis since my schooldays, and, although no champion, I was competent enough to have played tournament and representative tennis. I confessed to the Oriel captain that I had played a little tennis and was promptly asked to go out to the sports ground where the college experts would give me a trial. As it happened, I thrashed the college experts and was immediately accepted as a worthwhile member, a position made secure by my election to the University Lawn Tennis Club in my first term. But whatever the reason, I had three very happy years in Oriel.

Robert Robinson had come to Oxford just a year before I joined him, but already the Dyson Perrins Laboratory was a hive of activity. He had brought with him a group of research men of various nationalities, some pre- and some postdoctoral, and there was an air of excitement in the laboratories. Robinson himself was at the height of his powers and bubbled over with ideas. I had never met him until I went to join him in September 1931 and I still recall with amusement our first encounter in his office. He was seated at his desk writing, and when I came in he looked up and said ' So you've come to do research?' whereupon I replied simply 'Yes.' 'Well,' he said, 'you know I am interested in anthocyanins and for our synthetic studies we need various omega-hydroxyacetophenone derivatives; now I would like you to make some veratroyl chloride and see if you can convert it with diazomethane to a diazoketone and thence to the hydroxyketone.' He then picked up his pen, evidently finished with me. As I was still standing there he looked up and, seeing my rather puzzled expression, said 'What's the trouble?' 'That doesn't sound much of a problem,' I said, 'what about the research I have to do?' He spluttered a bit. 'What? Who are you?' 'My name is Todd.' 'Good God,' he said, 'I thought you were a Part II undergraduate!' He then started to chat about work and took me off to instal me in a small laboratory for two people adjacent to his own, where, incidentally, he also installed my Frankfurt friend Bertie Blount who was to work in the alkaloid field.

Blount and I occupied that laboratory for the next three years and, probably because of its proximity to his office and laboratory, we saw a lot of Robinson - much more than did most of his collaborators elsewhere in the building. We used to brew tea at about four in the afternoon and on most days Robinson would drop in and join us for a concerted attack on the Times crossword puzzle and a gossip about current chemical interests. It was during one of these 'tea and puzzle' sessions that I made the real breakthrough that opened the way to the synthesis of all the major diglucosidic anthocyanins. When I got to Oxford, one of the main stumbling blocks in efforts to synthesise such flower pigments as, for example, cyanin, pelargonin and malvin, was the total failure that had attended all efforts to make the 2-glucoside of phloroglucinaldehyde. Robinson was thinking up some very roundabout procedures to get out of this difficulty, but it seemed to me that since one could put a benzoyl group directly into the 2-position of phloroglucinaldehyde one ought to be able to put in a glucose residue. So I started in to condense acetobromoglucose with unprotected phloroglucinaldehyde; I tried all sorts of tricks, but I could get nothing but intractable syrups and gums. One day, however, I had a methanolic solution of one such gum in a small conical flask and was concentrating it by dipping it from time to time into a hot water-bath while at the same time having tea and doing the crossword puzzle with Robinson and Blount. The inevitable happened; I dipped the flask in for a little too long so that the solution boiled violently and, probably because it was rather hot, the flask slipped from my fingers and fell into the water-bath. I fished it out and put it over among the dirty glassware which I intended to clean up the following morning; to my astonishment when I came to do this the next day I noticed that the walls of my small flask were covered with crystals. They were indeed crystals of 2-beta-tetra-acetyl-D-glucopyranosyl-phloroglucinaldehyde! Henceforth, with seeding material available, there were no further problems and the way to the anthocyanins was wide open. I don't know what moral, if any, to draw from that story, but at least it explains why, in a later edition of a well-known chemical textbook, it is recorded that the 2-glucoside of phloroglucinaldehyde is best crystallised by diluting its concentrated methanolic solution with a large volume of hot water!