He hasn't died yet.
Doctor Clayton died in 1947.
Doctor Greenwood died in 1951.
The Doctor has died many times, but as a Time Lord, he regenerates into a new incarnation each time.
John Jones - doctor - died in 1791.
Alexander Fleming - doctor - died in 1875.
Alexander Hamilton - doctor - died in 1756.
John McClelland - doctor - died in 1875.
Francis Badgley - doctor - died in 1863.
Robert Hale - doctor - died in 1767.
Jacques d'Amboise - doctor - died in 1603.
James Jamieson - doctor - died in 1916.