Here is another reaction involving the activation of a carbon hydrogen bond where after the activation the alkane can be functionalized through the addition of iodine into the system under liquid nitrogen.  The study was performed out of my home department of chemistry at the University of British Columbia done by Peter Legzdins, Jenkins Y.K. Tsang, and Miriam S.A. Buschhaus in 2007.  The tungsten complex was particularly a tungsten allyl nitrosyl complex, which allows the linear ƞ3 alkane to be attacked by the I2 in creating the selective alkyl halide at the terminal position (1-iodopentane here specifically).