Synthesis and structure of Ag(1-Me-12-SiPh3-CB11F10):: Selective F12 substitution in 1-Me-CB11F11- and the first Ag(arene)4+ tetrahedron

The selective substitution of the antipodal F atom in 1-Me-CB11F11-with a SiPh3 moiety led to the isolation and structure determination of the cesium(I) and silver(I) salts of the 1-Me-12-SiPh3-CB11F10- anion. The silver salt contains both a nearly trigonal-planar Ag(arene)(3)(+) cation and the first example of a Ag(arene)(4)(+) cation.