In 1977, the Priestley Medal was awarded to Henry Gilman by the American Chemical Society “to recognize distinguished services to chemistry,” the Society’s most prestigious award.

His main area of research was in the Organometallic Chemistry area of Grignard reagents where he developed numerous Organometallic reagents, building a reputation for Iowa State as pioneering in the field.

His research interests also included heterocycles, polynuclear hydrocarbons, antimalarials, as well as long-chain aliphatic compounds. During World War II, Dr. Gilman was a consultant on the Manhattan Project for the atomic bomb. He set the groundwork for the growing interests of organometallics among chemical industries after the war, setting the stage for further development in the areas of plastics and Organosilicon. He wrote over 750 research publications and authored a four volume text entitled; Organic Chemistry, along with co editing the text Organic Synthesis.