Earlier Friday, the Blackhawks acquired defenseman Christian Ehrhoff from the Los Angeles Kings for defenseman Rob Scuderi.
Fleischmann, 31, has 10 goals and 20 points in 57 games this season with Montreal; half of his goals came in November, including two against the Jets on Nov. 1. He has 133 goals and 330 points in 638 NHL games, and four goals and nine points in 35 Stanley Cup Playoff games. Fleischmann is in his 11th NHL season; he also played for the Washington Capitals (2005-10), Colorado Avalanche (2010-11), Florida Panthers (2011-14) and Anaheim Ducks (2014-15).
Weise, 27, has an NHL career-high 14 goals and 26 points and was second on the Canadiens with 108 hits. He has 37 goals and 85 points in 314 games over six NHL seasons with the New York Rangers (2010-11), Vancouver Canucks (2011-14) and Montreal (2014-16). He has five goals and 10 points in 34 playoff games.
Danault, 23, has one goal and five points in 30 games with Chicago this season, and one goal and two points in six games with Rockford of the American Hockey League. He played in two games with Chicago last season.
Canadiens general manager Marc Bergevin was with the Blackhawks when they drafted Danault at No. 26 of the 2011 NHL Draft.
"Phillip Danault is a young and gifted player who will be part of our core group of young forwards for many years to come," Bergevin said. "I am very pleased to have him join our organization."
