There are three other structural isomers of 1-butanol: 2-butanol (sec-butyl alcohol), 2-methyl-1-propanol (isobutyl alcohol), and 2-methyl-2-propanol (tert-butyl alcohol). 2-Butanol, or sec-butanol, or sec-butyl alcohol, or s-butyl alcohol, is a four-carbon chain, with the OH group on the second carbon.
Chemicals of this type: Ethanol
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