Barton was born in Gravesend, Kent, He attended Gravesend Grammar School (1926–29), The King's School, Rochester (1929–32), Tonbridge School (1932–35) and Medway Technical College (1937–39). In 1938 he entered Imperial College London, where he graduated in 1940 and obtained his PhD degree in Organic Chemistry in 1942.
From 1942 to 1944 he was a government research chemist, from 1944 to 1945 he was with Albright and Wilson in Birmingham. He then became Assistant Lecturer in the Department of Chemistry of Imperial College, and from 1946 to 1949 he was ICI Research Fellow.