tertbutyyliryhmän

Tertbutyyliryhmä, also known as tert-butyl group, is a branched alkyl substituent with the formula -C(CH3)3. It is derived from isobutane by removing one hydrogen atom from the tertiary carbon atom. This group is characterized by a central carbon atom bonded to three methyl groups and the rest of the molecule. Its steric bulk makes it a significant factor in the reactivity and properties of organic compounds.

The tert-butyl group is a common protecting group in organic synthesis, particularly for alcohols and amines. Its large size shields the functional group it is attached to, preventing unwanted reactions. It can be removed under acidic conditions, regenerating the original functional group. Due to its steric hindrance, it can also influence the regioselectivity and stereoselectivity of reactions. For example, in electrophilic aromatic substitution, a tert-butyl group on a benzene ring will direct incoming electrophiles to the ortho and para positions.

The tert-butyl group is also found in various commercially important compounds, including antioxidants like BHT (butylated hydroxytoluene) and pharmaceuticals. Its presence often increases the solubility of a molecule in nonpolar solvents and can enhance its stability. The tert-butyl cation, formed by the removal of an electron from the tert-butyl group, is a relatively stable carbocation due to hyperconjugation from the methyl groups, further contributing to its utility in certain chemical processes.