Hydrocarbons with only 4 carbon atoms
Final update, all earlier edits incorporated.

Groundrules: Considering compounds with:


only carbon and hydrogen
only 4 bonds to carbon


There are 37 isomers without considering trans isomers; 49 when trans isomers are included.  Also, many of these compounds seem extremely unstable and therefore unlikely to exist.

Note to self: check back in 20 years and see how many of the unlikely ones have been detected.



Names by row:


butane, isobutane
but-1-ene, but-2-ene, 2-methylpropene
buta-1,3-diene, buta-1,2-diene, buta-1,2,3-triene
but-1-yne, but-2-yne, but-1-ene-3-yne, buta-1,3-diyne
methylcyclopropane, 2-methylcyclopropene, 1-methylcyclopropene, methylenecyclopropane, methylenecyclopropene, methlycyclopropadiene
methylcyclopropyne, methlenecyclopropyne
cyclobutane, cyclobutene, cyclobuta-1,2-diene, cyclobuta-1,3-diene, cyclobutatriene, cyclobutatetraene, cyclobutyne, cyclobutenyne, cyclobutadiyne
bicyclobutane, bicyclobut-1(3)-ene, bicyclobut-1(2)-ene, bicyclobuta-1,3-diene, bicyclobuta-1,2-diene
tetrahedrane, tetrahedrene, tetrahedradiene