The deal was announced hours before the Wild faced the Phoenix Coyotes in Arizona.
The Rangers have been looking for depth at forward to complement their top line of Rick Nash, Brad Richards and former Wild star Marian Gaborik. New York is also dealing with the loss of captain Ryan Callahan, who is currently sidelined by a dislocated shoulder.
The 27-year-old Powe has yet to record a point in eight games this season. He had six goals and seven assists while playing in all 82 games last season with the Wild. He played 204 games with the Philadelphia Flyers before joining Minnesota last season.
Rupp will provide Minnesota with a veteran, physical presence. In 565 NHL games over 10 seasons with New Jersey, Phoenix, Columbus, Pittsburgh and the Rangers, the 33-year-old winger has 53 goals, 41 assists and 765 penalty minutes. Rupp scored the Stanley Cup-winning goal for New Jersey in 2003.
Palmieri, 23, has 10 goals and 21 points in 40 games with Houston of the AHL. He played nine games with the Wild last season and has 13 goals and 25 points in 87 NHL games with New Jersey and Minnesota.
He has been assigned to Connecticut of the AHL.