Multiple substitutions on (η⁶-arene)tricarbonylchromium(0) complexes

The treatment of representative (η⁶-arene)tricarbonylchromium(0) complexes 1a-c and 4 with 3 equivalents of LiTMP followed by an electrophilic quench with Me₃SiCl provided a series of trisilylated complexes 2a-c and 5a. The use of Me₃SnCl and Ph₂PCl as electrophile also yielded unusual trisubstituted complexes 13a and 13b. The X-ray crystallographic structure of complex 13b is reported. Deuteration studies using deuteroacetic acid as the electrophile led to the observation of a trideuterated species presumably derived from a trianionic species formed during the reaction. Efficient disubstitution was observed when complexes 7, 9 and 11 were treated with 3 equivalents of LDA followed by an electrophilic quench with Me₃SiCl.