Rotate 45 degrees a profile

Hi every one, dose exist a way for rotate of 45 degrees a mesh without distorting ? For example costraint rotate script works well but need a face i found the shortcut ctrl+shift+alt +1 or -1 but works only along x axis have no effect along the y axis.

show some pictures
you could simple rotate it and then re scale by 1/ Radical 2

happy bl

thank you for your reply Ricky i would rotate like this video ,unlucky after rotate the vertex and extruding along the axis ortogonal , i cannot rotate again

excuse me the exact command is ctrl+alt+shift+s +/-1 (shear from menu transform)

Solved, i have only to press the axis after the command