Full list based on WookiepediaWookieepedia, Quora and extensive Googling of other sources. "{}" shows canon sources for the information about apprenticeship.
- Darth MaulDarth Maul { Episiode IEpisiode I }
- VergereVergere { Legacy of the Force: Betrayal }
- Darth Tyranus/Count DookuDarth Tyranus/Count Dooku { EpisideEpisode II }
- Garth EzzarGarth Ezzar { Destruction RPG }
- Darth Vader/Anakin SkywalkerDarth Vader/Anakin Skywalker { Episode III - VI }
- Ferus OlinFerus Olin (informal apprentice) { The Last of the Jedi: Secret Weapon }
- LumiyaLumiya { Jedi vs. Sith: The Essential Guide to the Force }
- Luke Skywalker when Palpatine was in clone body { Dark Empire 5: Emperor Reborn }
Please note that aside from Maul; Tyranus and Vader, none of these are Disney Canon - they are all Legends canon only.
All 3 Disney canon apprentices had apprentices of their own (Maul: Savage Opress; Tyranus: a whole buncha whole bunch; Vader: a whole buncha whole bunch but IIRC none are Disney canon). It's not clear if Savage Opress strictly violated the Rule of 2 as they didn't meet until after Maul was de-apprenticed by Obi-Wan's lightsaber.
He also had a bunch of people he trained who were not strictly speaking "Apprentices", such as (incomplete list of examples)
- Emperor's Hands (e.g. Mara JadeMara Jade)
- Prophet CronalCronal etc...
- Adepts who weren't apprentices, e.g. an unknown Niktounknown Nikto { Book of Sith: Secrets from the Dark Side }