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Tetra-tert-butylmethane

Tetra-tert-butylmethane is a hypothetical organic compound with formula CH, or ((HC-)C-)C. It would be an alkane, specifically the most compact branched isomer of heptadecane. The systematic name is 3,3-Di-tert-butyl-2,2,4,4-tetramethylpentane.

This compound is of interest because it is believed to be the smallest saturated and acyclic hydrocarbon that cannot exist (due to steric hindrance). However calculations suggest that the molecule would be stable, with C–C bonds of 0.1661 nm — longer than the typical C−C bond but still shorter than those found in some other real molecules.