Some recent examples of the use of weakly coordinating carborane anions to isolate reactive cations include the following. Currently, the icosahedral carborane with eleven chlorine substituents, CHB 11 Cl 11 - , is the most inert, least coordinating anion for trialkylsilylium ion chemistry. Carborane anions have helped solve the "silylium ion problem".

X-ray crystallographic proof of the existence of the silylium ion in
[Si(mesityl)3+][CHB11Me5Br6-]·C6H6. See Kim et al. Science 2002, 297, 825.

Characterization of a nearly linear 3-center-2-electron bond
in [Me 3 Si-H-SiMe 3 + ][CHB 11 Cl 11 - ]. See Hoffmann et al. Chem. Commun. 2005, 767.

The first example of SO 2 coordination to silicon, in
Et 3 Si(SO 2 )][CHB 11 Me 5 Br 6 ]. See Hoffmann et al. Chem. Commun. 2005, 767.

The structure of the C 59 N + cation (isoelectronic to C 60 )
in [C 59 N + ][Ag(CHB 11 Cl 6 ) 2 - ]. See Kim, et al. J. Am. Chem. Soc . 2003 , 125 , 4024 .

The B(subpthalocyanine) + cation in [B(subPc) + ][CHB 11 Me 5 Br 6 - ].
See Kato et al. Heteroatom Chem. 2006, 17, 209.

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