Carbon-hydrogen bonds. especially those of saturated ($) carbon ccnters.
arc normally considered to be chemically inert . There is a rapidly
increasing body of evidence. however. which shows that C-H bonds can
act as ligands to transition metal centers by formation of three.center . twoelectron
bonds (3c-2e) and that the extent of the interactions is such as to
have a marked effect on the molecular and electronic structure and hence
the reactivity of the molecule .