Isobutane diprotonated

Carboxoninm ions, for example, do not react with alkanes. However, in superacid solution acetaldehyde (or acetone), for example, readily reacts with isobutane involving diprotonated, highly reactive carbocationic species. 

Diprotonated ra-butane and isobutane cations (C4H122+) have been computed by Olah et al.788 Two distonic dications [the 1 -//,4-//-di protonated (476) and the terminal C—H and C—C diprotonated (477) forms] were found to have energy minima (MP2/6-31G level), with structure 476 being more stable by only 1.3kcalmol 1. 

For diprotonated isobutane (C4H122+) the structures found as stable minima are analogous to those computed for diprotonated propane (C3H102+). Again, structure 478 (a distonic dication) is 17.7 kcal mol 1 more stable than structure 479 (a gitonic dication), whereas structure 480 is only slightly less stable than 478 (2.6 kcal mol-1).788... 

Olah et al. have computed diprotonated n-butane and isobutane structures fC I Only two structures, two distonic cations [the 1 -//,4-//-di protonated... 

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