Willstätter was born into a Jewish family in Karlsruhe. He was the son of Maxwell Willstätter, a textile merchant, and his wife, Sophie Ulmann. He went to school at the Karlsruhe Gymnasium and, when his family moved to Nuremberg, he attended the Technical School there. At age 18 he entered the University of Munich to study science and stayed for the next fifteen years. He was in the Department of Chemistry, first as a student of Alfred Einhorn—he received his doctorate in 1894 - then as a faculty member. His doctoral thesis was on the structure of cocaine. Willstätter continued his research into other alkaloids and synthesized several of them. In 1896 he was named Lecturer and in 1902 Professor extraordinarius. In 1905 he left Munich to become professor at the ETH Zürich and there he worked on the plant pigment chlorophyll. He first determined its empirical formula. In 1912 he became professor of chemistry at the University of Berlin and director of the Kaiser Wilhelm Institute for Chemistry, studying the structure of pigments of flowers and fruits. It was here that Willstätter showed that chlorophyll was a mixture of two compounds, chlorophyll a and chlorophyll b. He lived in the Dahlem neighborhood near other scientists. In 1915 his friend Fritz Haber asked him to join in the development of poison gasses. Willstätter would not work on poisons but agreed to work on protection. He and his coworkers developed a three layer filter that absorbed all of the enemy's gasses. Thirty million were manufactured by 1917 and Willstätter was awarded the Iron CrossSecond Class. In 1916 he returned to Munich as the successor to his mentor Baeyer. During the 1920s Willstätter investigated the mechanisms of enzyme reactions and did much to establish that enzymes are chemical substances, not biological organisms. In 1924 Willstätter's career came to "a tragic end when, as a gesture against increasing antisemitism, he announced his retirement." According to his Nobel biography: "Expressions of confidence by the Faculty, by his students and by the Minister failed to shake the fifty-three year old scientist in his decision to resign. He lived on in retirement in Munich....Dazzling offers both at home and abroad were alike rejected by him." His only research was with assistants who telephoned their results. Despite pleas for him to move to Jerusalem or to Switzerland earlier in the 1930s, Willstätter did not flee from Germany until 1939. In 1939 Willstätter emigrated to Switzerland. He spent the last three years of his life there in Muralto near Locarno writing his autobiography. He died of a heart attack in 1942. Willstätter's autobiography, Aus meinem Leben, was not published in German until 1949. It was translated into English as From My Life in 1965.
Anecdote
In 1911 the fledgling American chemist Michael Heidelberger went to work for a year with Willstätter in Zurich. Willstätter helped his somewhat impecunious American student by sharing the cost of laboratory supplies with him, arranging that when expensive materials, such as silver nitrate, were to be bought, it was his turn to pay, while Heidelberger took turns buying cheaper materials like sulfuric acid. "Better training than that you couldn't have," Heidelberger summed up his experience with Willstätter. They remained friends for life.
Family
In 1903, he married Sophie Leser, who died in 1908. They had two children.
Honours
In 1965, the school in Nuremberg he had attended named itself Willstätter-Gymnasium, in his honour.
