In a further attempt to use CBS’s powerful prime-time line-up to increase Ms. Couric’s audience, and to showcase her skills as an interviewer, the network said on Thursday that it has given over its 9 p.m. hour to her on Feb. 4 for a special pegged to CBS’s broadcast of the Grammy Awards on Feb. 8. On the program, “Katie Couric: ‘All Access’ Grammy Special,” Ms. Couric is scheduled to interview the singers Justin Timberlake (with whom she golfs on screen), Lil Wayne (with whom she bowls), Katy Perry and Taylor Swift