Background
William Jackson Pope was born on October 31, 1870, in London, England. Pope’s parents, William Pope and Alice Hall were staunch and active Wesleyans who had eight children, of whom William was the eldest.
1913
Brussels, Belgium
Pope amongst the participants of the Second Solvay Conference on Physics that took place in Brussels.
1914
William Pope received the Davy Medal of the Royal Society.
1918
Pope was awarded the Most Excellent Order of the British Empire, which is a British order of chivalry, rewarding contributions to the arts and sciences, work with charitable and welfare organizations, and public service outside the civil service.
Royal Society, 6–9 Carlton House Terrace, London, England, United Kingdom
Pope was elected a Fellow of the Royal Society (FRS) in June 1902.
Sir William Jackson Pope
City and Guilds of London Institute, Kensington, London, England, United Kingdom
Pope studied at City and Guilds of London Institute, South Kensington.
The Royal Society of Chemistry (RSC), Burlington House, London, England, United Kingdom
Pope was a member and served as president of the Chemical Society for 1918 and 1919.
William Jackson Pope was born on October 31, 1870, in London, England. Pope’s parents, William Pope and Alice Hall were staunch and active Wesleyans who had eight children, of whom William was the eldest.
In 1878 Pope entered the Central Foundation School, in London, where his ability to learn rapidly gave him leisure at the age of twelve to carry out simple chemical experiments in his bedroom. Pope left school in 1885 with full marks on his final examinations in theoretical and practical chemistry and in theory of music and obtained entrance scholarships to Finsbury Technical College and the City and Guilds of London Institute, South Kensington. At the latter, he studied under H. E. Armstrong. A firm believer in the heuristic method of teaching, Armstrong forbade his students to take any examinations, so they ultimately departed without degrees.
In 1897 Pope became head of the chemical department of the Institute of the Goldsmiths’ Company at New Cross.
In 1901 Pope became head of the chemical department of the Municipal School of Technology and professor of chemistry at Manchester, and in 1908 he was appointed professor of chemistry at the University of Cambridge, a post he held until his death. At the time of his election, only the major departments were headed by a professor; and the appointment of Pope at the age of thirty-eight caused some surprise in nonchemical circles.
In the following years, the Pope’s advancement of chemistry in various directions was recognized by the conferment of the freedom and livery of the Goldsmiths’ Company by special grant in 1919, and he served as prime warden for 1928–1929.
Pope’s first investigation, in collaboration with H. E. Armstrong, was an attempt to obtain a crystalline derivative of pinene. Following some very old work of Ascanio Sobrero, they exposed the terpene fraction of oil of turpentine to moist oxygen in sunlight. The solid deposit, which when purified had the composition C10H18O2, was called sobrerol. This compound was optically active, and the dextro and levo forms were isolated from turpentines of various origins and were studied in detail. For this purpose, the Pope’s knowledge of crystallography and his skill with the goniometer were of great assistance to Armstrong.
Pope was then joined by F. S. Kipping, with whom he worked for several years. They showed that camphor was sulfonated by fuming sulfuric acid and by chlorosulfonic acid, which gave the corresponding sulfochlorides, compounds of exceptional crystallizing power. Furthermore, these sulfochlorides and sulfobromides lost sulfur dioxide when heated, forming the corresponding halogenocamphors, which they termed π-derivatives because of their pyrogenic formation. Furthermore, Kipping showed that the sulfonation had occurred on one of the gem-dimelhyl groups and (on the basis of J. Bredt’s camphor formula) on the 8-methyl group - that is. on the methyl group furthest from the carbonyl group. Consequently, the acid known as α-bromo-π-camphorsulfonic acid should be termed 3-bromocamphor-8-sulfonic acid.
A further investigation produced several new halogenocamphors. The study of these compounds, their sulfonic acids, and the conditions of their racemization revealed a number of points of crystallographic and theoretical interest and of the particular relationships that Kipping and Pope termed pseudoracemism.
Pope and Kipping also investigated the crystallization of sodium chlorate from aqueous solution, whereby dextro and levo crystals are deposited in virtually equal quantities. The activity here must be due to the arrangement of the molecules in the crystal, since the molecule is symmetric. Each crystal, when dissolved in water, therefore, gives an inactive solution. In an asymmetric environment, such as an aqueous solution of glucose, the weights of the deposited dextro and levo crystals of the chlorate are no longer equal. The investigation of this subject and later of the similar behavior of ammonium sodium tartrate in considerable detail was greatly aided by Pope’s crystallographic skill. This fruitful partnership ended when Kipping became professor of chemistry at University College, Nottingham, and Pope became head of the chemical department of the Goldsmiths’ Institute at New Cross.
At the Goldsmiths’ Institute, Pope and S. J. Peachey investigated “tetrahydropapaverine“, which hitherto had resisted optical resolution. Pope recalled his earlier experience with bromocamphorsulfonic acid; and with the salt of this acid he readily resolved the base, which was later found by F. L. Pyman to be dihydro papaverine. This was one of the earliest resolutions using bromocamphorsulfonic acid, and a number of resolutions of basic compounds or dissymmetric cations using salts of camphorsulfonic and bromocamphorsulfonic acids followed. These acids were of outstanding value at this stage of stereochemical elucidation. Pope then started a new line of investigation, which was conspicuously successful and immensely increased his reputation. Compounds that showed optical activity in solution had hitherto all contained one or more asymmetric carbon atoms.
Pope and J. Read, after a very carefully controlled repetition of Le Bel’s work, decided that he had never obtained the chloride. They then prepared Wedekind’ iodine, converted it into the d-camphor-sulfonate, and by fractional crystallization obtained the diasteroisomerides, from which they isolated the optically active iodides and bromides. This proved “that quaternary ammonium derivations in which the five substituting groups are different, contain an asymmetric nitrogen atom which gives rise tp antipodal relationships of the same kind as those correlated with an asymmetric carbon atom". The chemical and optical properties of Wedekind’s iodide and salts with anions were examined in considerable detail.
This type of work was extended by combining ethyl methyl sulfide with ethyl bromoacetate to yield Methylethylthetin bromide, which was converted into the d-bromocamphor sulfonate; recrystallization similarly gave the d-and l-forms of methylethylthetine bromide. The analogous phenylmethylselenetine bromide was similarly resolved into optically active forms, again via the d-bromocamphorsulfonatei. The appalling and persistent stench of selenides of type R2Se very seriously delayed this work.
Compounds of tin were next investigated. These compounds required careful manipulation because they were highly toxic in both the liquid and the vapor states. Pope and Peachey were able, however, to prepare methyl ethyl propyltin iodide. This liquid was volatile without decomposition and was soluble in nonpolar solvents; thus it was a covalent compound. It reacted with silver d-camphor sulfonate to give the corresponding sulfonate, which was soluble in water and was clearly a salt. Evaporation of an aqueous solution of the sulfonate gave solely the d-tin d-sulfonate, indicating ready racemization of the cation of the salt and a marked difference in the solubilities of the two diastereisomerides. Treatment of the active sulfonate in aqueous solution with potassium iodide precipitated the active iodide, which readily underwent racemization.
Pope and C. S. Gibson found that ethyl magnesium bromide reacted with auric tribromide to give two compounds considered to be (C2H5)2AuBr and (C2H5)2AuBr. Many years later Gibson and his collaborators reinvestigated these gold compounds and found that they were both dimeric bridged compounds.
In 1906–1910 Pope devoted a great amount of time to attempt, with W. Barlow, to correlate chemical constitution and crystal structure. The “valency-volume theory of crystal structure,” which they developed, states, in brief, that the space that an atom occupies in a crystal is proportional to its valency. The labors of Barlow and Pope revealed many factors that have helped the evolution of modern crystallography, but the main theory has been discarded.
Pope, in collaboration with W. H. Perkin, Jr., therefore, attempted to synthesize l-Methyl cyclohexylidene-4-acetic acid, a compound similar to the allene hydrocarbon but with one double bond of the latter expanded to a six-member ring. This synthesis was achieved but by a laborious method giving a low overall yield.20 By coincidence. W. Marckwald and R. Meth had been investigating the synthesis of the acid; their product, certainly different from Perkin and Pope’s acid, was later identified as the isomeric acid.
Before 1914 no one had synthesized and resolved a compound having only one carbon atom, which must necessarily be asymmetric. After considerable work Pope and J. Read synthesized chloroiodomethane sulfonic acid and resolved it, using initially hydroxyhydrindamine and later brucine for this purpose. The acid had [M]5461 + 43° and considerable optical stability: its aqueous solution could be boiled for two hours without loss of activity.
At the outbreak of World War I, Pope was in Australia presiding over Section B (chemistry) of the British Association for the Advancement of Science. He immediately returned to England and was soon involved in chemical problems, one of which was the preparation of photographic sensitizers. Photographic plates at that time were prepared with a silver bromide-silver iodide emulsion, which was sensitive only in the ultraviolet, violet, and blue regions; aerial photographs taken at dawn in predominantly red light was almost useless.
Quotations: "Chemists must unite in order to force upon the reluctant world the power of their discoveries."
Pope was elected a Fellow of the Royal Society (FRS) in June 1902. He was also a member and served as president of the Chemical Society for 1918 and 1919 and was a member of the British Association for the Advancement of Science.
While at school Pope developed great skill as a photographer - many of his early photographs were in perfect condition fifty years later. Pope readily learned foreign languages and became proficient in French and German in his teens and in Italian somewhat later. He was known, on the eve of his departure to deliver an important lecture in Paris, to sit down at his typewriter, think deeply for a few minutes, and then rapidly type the complete lecture in French.