Chemical Relations: William and Lawrence Knox, African American Chemists

Brothers William and Lawrence Knox discovered that earning PhDs in chemistry was not enough to overcome discrimination. World War II opened doors to a wider chemical world, but racism continued to shadow their lives.

On New Year’s Day 1940 Lawrence H. Knox received his PhD in organic chemistry from Harvard University. One of a select cohort of 26 to receive that particular degree in the United States that year, Lawrence belonged to an even more select group: he was one of only 30 African Americans to receive a PhD degree in all branches of chemistry since 1916. Astoundingly, another member of that group was Lawrence’s older brother, William Jr., who received his PhD in physical chemistry from the Massachusetts Institute of Technology in 1935.


Lawrence Knox at Bates College, undated.

Lawrence Knox at Bates College, undated.

The Edmund S. Muskie Archives and Special Collections Library

That one family should produce almost 7% of all black PhD chemists over a 25-year period is remarkable—especially a family with its roots in the slave-holding South. Beginning in the 1820s in North Carolina, where teaching slaves to read was a criminal offense, and stretching to the 1930s in New England, where a few black students attended the country’s elite universities, each generation of the Knox family climbed another rung on the ladder of success.

Yet William’s and Lawrence’s talents, hard work, and superb qualifications could not insulate their lives from the pervasive racism of American society. While World War II opened doors to a world beyond the black education ghetto, postwar patterns of discrimination molded both of their lives as chemists. Each brother confronted rebuffs and humiliations; each made a distinct contribution to chemistry and to American society.

Climbing toward Chemistry

The brothers’ grandfather, Elijah Knox, was born into slavery in North Carolina in the 1820s. Elijah became a skilled carpenter and bought his freedom in 1846. He moved north, eventually settling in New Bedford, Massachusetts—an important stop on the Underground Railway with a long-established African American community. Family histories and birth records suggest that Elijah’s sister was Harriet Jacobs, author of a famous slave narrative of resistance, Incidents in the Life of a Slave Girl.

Elijah’s son, William Jacob, established the family tradition of upward mobility through education. After receiving the highest grade on the New Bedford civil-service exam in 1903, he obtained a post-office position in 1905. William Jacob and his wife, Estella, had five children. The two girls were steered toward vocational training while the three sons (William, born 1904; Lawrence, born 1906; and Clinton Everett, born 1908) were sent to college. (The youngest son received his PhD from Harvard in the same year as Lawrence and eventually served as U.S. ambassador to Dahomey and Haiti.)

When William entered Harvard in September 1921, the university excluded students of color from the freshman dormitories. Many years later William lamented this denial of intellectual give-and-take with his classmates and, often, academic help from his professors. He felt robbed of a large part of his undergraduate experience. The bitterness over his exclusion never completely abated, lingering long after his 1925 graduation.

Further north Lawrence enjoyed a rich life as an undergraduate at Bates College in Lewiston, Maine. Like many other predominantly white American colleges that admitted students of color, Bates had a maximum quota of 3% for minorities, which included African Americans and Jews. Once admitted, Larry (as he was called), experienced little if any discrimination; he played football, joined the Jordan Scientific and Outing Clubs, and majored in chemistry. The 1928 Bates yearbook described Larry in doggerel: it begins, “The ‘Lord,’ a mighty man is he, and full well versed in chemistry,” and concludes, “At words and mischief he is best—both in the night and in the day!” Larry wrote a senior honors thesis investigating the Friedel-Crafts reaction between acid chlorides and aromatics, and graduated cum laude in 1928.

That one family should produce almost 7% of all black PhD chemists over a 25-year period is remarkable—especially a family with its roots in the slave-holding South.

Despite their degrees in science, the brothers faced limited employment prospects. Civil-service regulations shielded African American federal government workers from overt discrimination; segregated hospitals meant black doctors could find positions at black hospitals, while black colleges and universities offered teaching positions. Lawrence and William headed to the South to teach in historically black colleges. Their first encounters with legalized segregation left William, in particular, deeply disturbed. Fifty years after receiving his bachelor’s degree from Harvard, he wrote in his class report of his “unwillingness to continue to subject [himself] and [his] family to the indignities associated with living in the South.” The solution for both brothers was more education.

In 1928, after three years of teaching at Johnson C. Smith University in North Carolina (among whose alumni was Henry A. Hill, until this year the only African American president of the American Chemical Society), William went back to Cambridge, this time to attend MIT. In 1929 he earned an MS degree in chemical engineering, working on vapor-phase esterification of acids, and then returned to teaching, this time at Howard University, in Washington, D.C. After two years he returned to MIT for his PhD, working on the spectroscopy of the NO2/N2O4 system. Even with a doctorate, in the 1930s William’s career options were still limited to teaching at historically black colleges or universities. He returned to the South in 1935, this time to the Agricultural and Technical College of North Carolina, and after a year moved to Talladega College in Alabama, where he was head of the chemistry department.

Larry spent two years teaching at Morehouse College in Atlanta before heading to Stanford University in 1930. There he worked with Carl Noller on the reducing action of Grignard reagents, obtaining a MS degree after one year. And then, like William, he re-entered the world of chronically underfunded black colleges and universities, which were bereft of all but the most basic chemical glassware. In 1936, after teaching at the North Carolina College for Negroes in Durham for three years, he applied to and was accepted for doctoral work at Harvard. His first two years were supported by a fellowship from the General Education Board, which assisted African Americans seeking higher degrees.

Larry elected to work for Paul Bartlett, the U.S. leader in the new field of physical organic chemistry. Despite a prolonged illness during his first year, he earned his doctorate in 1940. Bartlett praised Larry’s perseverance and laboratory skills, calling him “one of the most productive” of his 15 lab workers. The resulting Bartlett/Knox paper was quickly recognized as a classic in physical organic chemistry and is still cited in current textbooks. Larry studied the mechanism of nucleophilic substitution in aliphatic compounds, a ubiquitous chemical and biochemical process. He had synthesized a compound that was incapable of reacting by either of the two then recently proposed reaction pathways. It proved inert even under strenuous conditions, lending strong support to the hypothesis that those were the only two pathways for nucleophilic substitution under ordinary conditions.

Despite producing what Bartlett described as the “neatest and prettiest job of any research student,” Larry’s skin color continued to trump his chemistry. With no other options Larry, PhD in hand, returned to teaching at North Carolina College for Negroes.

Opportunities of War

With America’s entry into World War II the growing need for trained personnel offered opportunities for many groups largely excluded from the chemical industry—women, Jews, and African Americans. Anxious to join the war effort, William contacted Willard Libby at Columbia, who was using corrosive uranium hexafluoride gas (UF6) to separate uranium isotopes for an atomic bomb.

William joined the unit in 1943 and spent two-and-a-half years working on corrosion problems. When the Corrosion Section’s leader left, Libby appointed William head of the all-white section. William later said that the war provided his first taste of true membership in an active scientific community. Arthur Holly Compton, Nobel laureate and leader of the Manhattan Project’s Metallurgical Laboratory, proclaimed that the atomic-bomb project had shown how “colored and white, Christian and Jew” could work together toward a common end. William had finally broken free of the preordained path for black chemists.

Larry’s chance came in 1944. Early that year Robert Woodward and William Doering published on the total synthesis of quinine, an antimalarial agent. Seeking to contribute to the war effort, Larry wrote to Doering, who was directing a quinine-related project for the Division of War Research. Doering, who knew of Larry’s work with Bartlett, hired him to work on the project.

After the war Larry found an industrial position with Nopco, a specialty chemical company in Harrison, New Jersey. In his three years there he was granted at least four patents. Like his brother William, Larry finally broke out of the black chemists’ “professional ghetto.”

For both brothers World War II created opportunities previously out of reach for black men. War also served as a catalyst for changing racial attitudes in the United States. The conspicuous bravery and commitment of many black servicemen, such as the Tuskegee Airmen, bolstered the claim of black Americans to full equality. In 1948 President Harry S. Truman integrated the armed forces; in 1955 Rosa Parks refused to give up her seat to a white person on a bus in Montgomery, Alabama. In this era African Americans faced both brutal challenges and increased possibilities. During the turbulent years of the civil-rights struggle William and Larry’s paths diverged.

William’s Postwar Career: Practicing Chemistry, Pursuing Civil Rights

Thanks to Libby’s personal recommendation, the Eastman Kodak Company offered William a position as a research associate in 1945. He was the second African American PhD chemist hired by Kodak, which was headquartered in Rochester, New York. William worked on introducing surfactants into photographic emulsions to improve the manufacturing process and raise the quality of photographic film; during his 25 years at Kodak he coauthored 3 journal articles and was granted 21 patents.

Though William’s career took off, his family life still suffered from the effects of racism. His attempts to find a decent home near a good school for his daughter, Sandra Audrienne, proved fruitless: the house initially offered to him was an abandoned brothel. Finally, a sympathetic white coworker bought a house under his own name and sold it to William. The strain of living in a sometimes hostile community took its toll, but William’s wife, Edna, would simply say of those who shut the family out, “It is their loss.” At home William talked little about the slights, rebuffs, and obstacles they all encountered, but in public life he set out to make sure that others were spared.

The strain of living in a sometimes hostile community took its toll, but William’s wife, Edna, would simply say of those who shut the family out, ‘It is their loss.’

William became a major figure in the Rochester civil-rights movement. Active in the local branch of the National Association for the Advancement of Colored People, he was also a founding member of the Rochester Urban League and sat on several civil-rights and antidiscrimination commissions. Convinced that education was indispensable in overcoming the effects of discrimination, William was instrumental in creating scholarships for minority students. His own painful experience trying to find decent housing propelled him into a leading role on the Housing Advisory Council and Urban League of Rochester.

Larry’s Postwar Career: Dedication to Chemistry

As with William, Larry found promotion via a prominent white scientist. In 1948 he received an invitation from Doering to become the resident director at the Hickrill Chemical Research Foundation in Katonah, New York. As a private venture created by philanthropists Sylvan and Ruth Alice Weil on their estate, the foundation specialized in long-term and speculative research where quick results were unlikely.

For Larry the move to Katonah was ideal, but not for his family. The area’s mostly poor and uneducated black residents lived in a marginal district called Greenville. Since white residents vehemently opposed the Knoxes living in the better part of town, the Weils built a home for the family on their estate—an isolating experience for Larry’s wife, Hazel, and their son.

At work Larry oversaw research projects and also worked at the bench. Doering described Larry as “the finest experimental coworker I ever had.” Larry could also inspire others, such as Maitland Jones Jr., a local teenager who worked summers at Hickrill and who became a professor of chemistry at Princeton University. Larry also influenced Caleb Finch, another summer worker, who went on to a professorship in neurobiology at the University of Southern California. Finch remembers Larry’s patience and kindness toward him as he learned the most basic of lab techniques. Finch was equally impressed by his “equanimity and composure during these excruciatingly difficult social and political circumstances.”

These circumstances included social isolation. Larry and Hazel joined St. Luke’s Episcopal Church in Katonah but were never invited into well-to-do members’ homes. Soon after their arrival they planned a party and sent out personal invitations—but no one came. In another instance Doering and Knox drove to an American Chemical Society meeting in Chicago (about 900 miles each way) and slept in the car because no motel would accept Larry as a guest, even in the North.

Since the Hickrill Laboratory was not constrained by the need for practicality or profit, the researchers could pursue fundamental issues. One question that had baffled chemists since the 19th century was why benzene (C6H6) and related ring compounds (so-called “aromatic” substances) were unusually stable and unreactive (a fact that did have many practical consequences).

In 1933 German theoretician Walter Hückel proposed a general theory based on the number of electrons in the ring compounds. Doering and Knox decided to test the theory experimentally by preparing C7H7+ (called the tropylium ion). Conventional thinking held that charged organic compounds, like the tropylium ion, would be reactive and difficult to isolate; Hückel’s theory predicted the opposite. Doering and Knox provided experimental support for Hückel’s theory, which explained a focal point of organic chemistry. Their work also pushed reluctant organic chemists toward greater reliance on theory.

In the late 1950s the foundation closed, and the estate was sold by the Weil children. Larry’s marriage also fell apart. After his divorce he married Anne Juren, the foundation’s white secretary, and took a position with Laboratorios Syntex S.A. in Mexico City. Part of the motivation for the move was his belief that a mixed marriage would fare better in Mexico than in the United States.

Although a small pharmaceutical company, Syntex had made a splash in the 1940s with the isolation of a sapogenin that could be readily transformed into progesterone. This discovery dropped the price of progesterone precipitously and led to the development of one of the first birth-control drugs. The 1950s and early 1960s were the “Golden Age” of steroid chemistry, and Syntex was a major player in the race to publish and patent new reactions, processes, and compounds.

Larry fit in well at Syntex, despite having no previous experience with steroids. He did have, however, a great deal of experience at the cutting edge of chemistry, a history of working harmoniously with colleagues, and exceptional laboratory skills. From 1960 to 1965 Larry coauthored 10 papers and was awarded over 40 patents related to steroid chemistry. At least two of the investigations harkened back to work done at Hickrill: steroids containing 7-membered rings and reactions of unsaturated steroids with halocarbenes.

In 1964, when the new company headquarters opened in Palo Alto, California, most of the expatriate staff relocated, but Larry and Anne opted to stay in Mexico where racial attitudes were relatively liberal. They adopted Naomi, a Mexican baby, but Larry did not live to see her grow up. He died from carbon monoxide poisoning in 1966, while working in a home office warmed by a kerosene heater.

Epilogue: A Tale of Two Brothers and a Wider Community

The struggles of Larry and William to gain professional acceptance and maintain personal dignity, stirring as they are, were not unique. Chemist Percy L. Julian and biologist Ernest E. Just shared similar stories. The Knox brothers stand out because they were two members of the same family who sought professions in scientific research, where prospects for African Americans were generally dismal. Those with an aptitude for science and a decent education usually opted for medicine, as Julian’s two brothers did.

The struggles of Larry and William to gain professional acceptance and maintain personal dignity, stirring as they are, were not unique.

The careers of the Knox brothers bracket those of Julian and Just. William spearheaded numerous civil-rights initiatives. Although he was a capable scientist who enjoyed his work, chemistry did not always claim his primary allegiance. He wrote that the bitter experiences of racial discrimination “have led to my active participation in efforts to establish a genuinely democratic society.” William was highly respected by his Kodak colleagues—known as “the man to consult about coating problems”—but his principal legacy is his record of civic action. The recipient of several awards for his work in the local community, he died in 1995.

By contrast Larry always prized working at the bench and, as far as we know, never involved himself in any social movement. A notice of his death in the Bates Alumnus carried the following excerpt from a eulogy delivered at Syntex: “His contribution to science is fundamental . . . his recent discoveries so important . . . that his name will remain forever in scientific literature. . . . He leaves us a unique example of dynamism and enthusiasm. . . . He will remain an example of courage and modesty.”

Nonetheless, William and Lawrence, brothers and scientists, each had to confront the racial discrimination that shadowed but never eclipsed their lives and careers.

Editors’ Note: Walter Hückel is named in this article as the theoretician who proposed a general theory based on the number of electrons in a ring compound. In fact, it was his brother Erich who proposed the theory. We regret the error.