As far as the canon goes, I found four relevant examples, listed in 'in-universe' chronological order:
1) In the Attack of the Clones movie, when Count <PERSON> has <PERSON> trapped on Geonosis, he tries to lure <PERSON> into helping him overthrow <PERSON>:
<PERSON>: What if I told you that the Republic was now under the control of the Dark Lord of the Sith?
<PERSON><PERSON><PERSON>: No, that's not possible. The Jedi would be aware of it.
<PERSON>: The dark side of the Force has clouded their vision, my friend. Hundreds of senators are now under the influence of a Sith lord called <PERSON>.
<PERSON>: I don't believe you.
<PERSON>: The viceroy of the Trade Federation was once in league with this Darth Sidious but he was betrayed ten years ago by the dark lord. He came to me for help. He told me everything. You must join me, <PERSON>, and together we will destroy the Sith!
Though there is some debate as to whether or not he was sincere in this request, see http://scifi.stackexchange.com/questions/74249/why-did-dooku-reveal-the-truth-to-obi-wan-on-geonosis
2) <PERSON> ordering Count <PERSON> to kill his assassin/apprentice, <PERSON>, in TCW 3x12:
Sidious: Lord <PERSON>.
<PERSON>: My master.
S: There is a disturbance in the force. 605
Your assassin, she has become very powerful.
D: Yes, my lord. She is quite important to me.
S: Too important. I can sense her powers growing stronger. I would hate to think you are training your own sith apprentice to destroy me.
D: Never. My allegiance is to you and you alone.
S: Then you must prove it. Eliminate her.
D: She's my most trusted ...
S: I said eliminate her!
D: As you wish, my lord.
3) The part mentioned by ncalmbeblpaicr0011 in TCW 3x13, taken with a grain of salt considering that <PERSON> had just ordered <PERSON> to get rid of his previous apprentice, and there wasn't anything further mentioned in TCW about <PERSON> trying to overthrow <PERSON>.
4) In the novelisation of Return of the Sith, by <PERSON>, you can find excerpts referenced in http://scifi.stackexchange.com/questions/5922/what-was-dookus-plan-for-the-battle-of-coruscant which discuss <PERSON>'s frame of mind towards <PERSON> at that point. 605