It is usually obtained by processing coal tar or petroleum, but can also be obtained by the thermal decomposition of several types of plants containing it, as explained in a namesake rule by Otto Wallach.  
Other than methane, this colorless, volatile hydrocarbon has the highest organic emission volume because it is emitted by photosynthetic leaves.  It yields butyl rubber when combined in small amounts of isobutene, while its polymerization can build-up nerol, citral, and farnesol.  It is usually obtained by processing coal tar or petroleum, but can also be obtained by the thermal decomposition of several types of plants containing it, as explained in a namesake rule by Otto Wallach.  FTP, name this compound, also known as 2-methyl-1,3-butadiene, the monomer of terpenes with chemical formula C5H8.
Other than methane, this colorless, volatile hydrocarbon has the highest organic emission volume because it is emitted by photosynthetic leaves.  
isoprene