Vegas received defenseman John Moore and forward Ryan Kesler in return for the forward.
Anaheim also received a conditional second-round pick in the 2023 or 2024 NHL Draft.
Dadonov has one season remaining on a three-year, $15 million contract ($5 million average annual value) he signed with the Ottawa Senators on Oct. 15, 2020 and can become an unrestricted free agent after next season.
He was traded to the Golden Knights by the Senators for defenseman Nick Holden and a third-round pick in the 2022 NHL Draft on July 28, 2021.
RELATED: [2021-22 NHL Trade Tracker]
Dadonov has scored 27 points (15 goals, 12 assists) in 62 games this season. He was tied for third on the Golden Knights in goals with forwards Max Pacioretty and Chandler Stephenson.
Selected in the third round (No. 71) of the 2007 NHL Draft by the Florida Panthers, Dadonov has scored 249 points (119 goals, 130 assists) in 397 games with the Panthers, Senators and Golden Knights and one assist in four Stanley Cup Playoff games.
Anaheim (27-26-11) is sixth in the Pacific Division, seven points behind Vegas for the second wild card into the playoffs from the Western Conference.
Moore was acquired by the Ducks from the Bruins in a trade for defenseman Hampus Lindholm on Saturday. Moore has one assist in seven games this season and has not played since Jan. 12. The 31-year-old has one season remaining on a five-year contract he signed with the Bruins on July 1, 2018 and can become an unrestricted free agent after next season.
Selected by the Columbus Blue Jackets in the first round (No. 21) of the 2009 NHL Draft, Moore has scored 118 points (38 goals, 80 assists) in 544 regular-season games with the Bruins, Devils, Arizona Coyotes, New York Rangers and Blue Jackets, and four assists in 49 playoff games.
Kesler has not played since March 6, 2019 because of a reoccurring hip injury and has said his playing career is over. He is in the final season of a six-year contract he signed with Anaheim on July 15, 2015.
Vegas (34-26-4) is fourth in the Pacific, two points behind the Edmonton Oilers.
