Pettersson gave Vancouver a 2-1 lead at 12:06 of the third, one-timing a pass from Bear below the right circle.
Pettersson then made it 3-1 at 13:09 with a power-play goal. He jammed in a rebound in the crease after Quinn Hughes' shot was redirected by Boeser and Andrei Kuzmenko.
Reichel cut it to 3-2 at 18:18, but Boeser scored into an empty net at 18:57 for the 4-2 final.
Canucks forward Aidan McDonough, who signed a two-year contract on March 13 following his senior season at Northeastern University, had one shot on goal in 10:03 of ice time in his NHL debut.
"It was awesome," McDonough said. "It was amazing, just to have so many friends and family here. To share with my best friend since first grade, [defenseman] Jack Rathbone, to be out there with me, and obviously to get the two points, it was amazing. Everything you can dream of."
NOTES: Canucks forward Vasily Podkolzin did not play after leaving Vancouver's 3-1 victory at Dallas on Saturday after blocking a shot. Tocchet said he is day to day … Blackhawks defenseman Jarred Tinordi left the game in the second period. "It's kind of a reoccurring injury he had earlier in the season with his hip," Chicago coach Luke Richardson said. "We'll know more by Tuesday, probably. … I just talked to the doctor there now and just said, we'll see how he is Tuesday."