Edwards hit 6 of 8 shots and all six free throws.
Purdue (30-6) will meet No. 3 seed Texas Tech in Friday's East Region semifinals in Boston.
Butler guard Kamar Baldwin missed a potential game-tying 3-point shot at the buzzer. Kelan Martin led Butler (21-14) with 29 points on 9-of-18 shooting. Baldwin added 14 points.
P.J. Thompson scored 14 points, hitting 6 of 9 shots. Carsen Edwards scored 13 points, but was 4 of 17 from the field. Dakota Mathias delivered 11 points, including a big 3-pointer late.
The Boilermakers had to play without senior center Isaac Haas, who suffered a fractured right elbow in the victory over Cal State Fullerton on Friday. The 7-foot-2 Haas, who averaged 14.7 points, was fitted for a brace. Officials ruled the brace did not meet safety standards.
Center Matt Haarms, replacing Haas, scored seven points and grabbed six rebounds.
Purdue shot 50 percent and Butler was right behind at 49.1 percent. The difference was Purdue making 11 of 24 3-pointers while Butler was 6 of 20 on 3s.
Vincent Edwards scored 12 points in the first half to help Purdue to a 40-36 lead. Edwards picked up his third foul with 3 seconds left in the first half.
Ahead by 54-51, the Boilermakers went on a 7-0 run to take a 61-51 lead with 10:19 to go.
The Bulldogs closed the gap to 70-65, but Purdue's Ryan Cline answered with a 3-pointer to push the lead to 73-65. Butler followed with a 6-0 run.
Mathias sank a 3-pointer with 17 seconds left to give Purdue a 76-71 lead. Martin's layup with three seconds left made it 76-73.
Purdue's Thompson then missed the front end of the one-and-one with 2.1 seconds left. That set the stage for Baldwin's miss.
The shooting was nearly identical in the first half. Purdue made 12 of 28 shots for 42.9 percent and Butler was 12 of 26 from the field for 46.2 percent. Purdue was 11 of 15 from the free-throw line while Butler made all seven foul shots.
The Boilermakers held a 20-13 first-half rebounding edge.
Butler led by as many as nine at 24-15 with 7:44 left. Purdue held a 25-12 advantage the rest of the half.
-- Field Level Media
Butler | Purdue | |
Kelan Martin 29 | Scoring | Vince Edwards 20 |
Aaron Thompson 4 | Assists | Dakota Mathias 4 |
Nate Fowler 5 | Rebounds | Matt Haarms 6 |
Kelan Martin 8 | Free Throws Made | Vince Edwards 6 |
Kamar Baldwin 2 | Steals | Nojel Eastern 1 |
Henry Baddley 1 | Blocks | Matt Haarms 2 |