Methyl group is the name given to the portion of an organic molecule that is derived from methane by removal of a hydrogen atom (-CH3). A methyl group can be abbreviated in chemical structures as -Me. The methyl group is one of the alkyl groups defined by dropping the -ane ending from the parent compound and replacing it with -yl. The methyl group is derived from the parent alkane, methane (HCH3) by removing one of the hydrogens. Methane has the molecular formula CH4. It is composed of a central carbon atom bonded to four hydrogen atoms (C-H). The term, methyl is a blend of the Greek words for wine, methy, and wood, hyle and was first used in reference to wood alcohol or methyl alcohol (CH3OH). The methyl group consists of a single carbon atom unit that is connected to a longer chain of carbon atoms or possibly a benzene ring.
Methane was originally called "marsh gas" because it was first isolated from the gas bubbling out of marshes. Methane is produced by certain microorganisms that grow in an oxygen-free environment such as sewage and mud. Natural gas is composed primarily of methane. When natural gas is mixed with steam and heated to a high temperature in the presence of a metal catalyst, synthetic gas composed of carbon monoxide (CO) and hydrogen (H2) is produced.
Synthetic gas is used industrially to make methanol (CH3OH). Methanol is an alcohol composed of a central carbon atom bonded to three hydrogens (C-H) and a hydroxyl group (-OH). It is used to make formaldehyde, methyl tert-butyl ether (MTBE) and other industrially important chemicals. Formaldehyde is a principal component of the resins that hold boards, such as plywood and particle board, together. Methyl tert-butyl ether (MTBE) is added to gasoline to increase its octane rating and to make it burn cleaner.
See also Alkyl group.