The opener's 162-run fourth-wicket partnership with nightwatchman Graham Onions helped the hosts recover from 78-3 to 240-4, when the latter fell lbw to Ravi Patel for a career-best 65.
Jennings' century came off 203 balls and included 12 boundaries.
Durham declared on 385-8, as Notts closed on 17-1, needing 300 more runs on the final day to secure victory.
Onions reached his maiden half-century just as Jennings passed three figures for the sixth time in the Championship this season - a Durham record he now shares with Michael Di Venuto and Paul Collingwood.
After Patel removed Onions, Luke Fletcher dismissed Collingwood and Michael Richardson cheaply before Imran Tahir bowled Stuart Poynter.
However, Jennings remained untroubled passing 150 off 284 balls and was ably assisted by Barry McCarthy (28 not out), which allowed Durham to declare when bad light briefly interrupted play shortly before the close.
Relegation-threatened Notts lost Jake Libby in the final over of the day, bowled by Onions.
The visitors began the match bottom of Division One and 35 points adrift of seventh-placed Durham, who have played one game fewer.
Keaton Jennings scored 171 not out as Durham set Nottinghamshire a target of 317 to win at Chester-le-Street.