The pair was awarded the Nobel Prize in Chemistry in 1950 for their work.

Diels was employed at the University of Kiel when he completed his Nobel Prize–winning work, and remained there until he retired in 1945.

Diels was born on 23 January 1876 in Hamburg, Germany, and moved with his family to Berlin when he was two years old.

He studied in Berlin at Joachimsthalsches Gymnasium before attending the University of Berlin starting in 1895.

While at university, Diels studied chemistry under Emil Fischer, eventually graduating in 1899.

He advanced quickly through the ranks at the school, eventually ending up as Department Head in 1913.

He remained at the University of Berlin until 1915, when he accepted a position at the University of Kiel, where he remained until his retirement in 1945.

It was during his time at Kiel, where he worked with Kurt Alder developing the Diels–Alder reaction, for which they were awarded the Nobel Prize in Chemistry in 1950.

Diels married Paula Geyer in 1909.

He died on 7 March 1954.

Nobel Lecture Description and Importance of the Aromatic Basic Skeleton of the Steroids Photo of Diels and Alder English Translation of Diels and Alder's seminal 1928 German article that won them the Nobel prize.