在有機化學中，烷基取代物是缺少一個氫的烷烴。烷基一詞故意不具體，包括許多可能的取代。無環(huán)烷基具有通式CNH2N+ 1。環(huán)烷基是由環(huán)烷烴通過從環(huán)上除去氫原子而得到的，具有通式CnH2n-1。通常烷基是大分子的一部分。在結構式中，符號R用于指定一個通用的（未指定的）烷基。最小的烷基是甲基，其分子式為CH3。
(5-Isopropyl-2-methoxyphenyl)boronic acid
Tetrakis(dimethylamino)diboron
4,4-Dimethyloxazolidine
Sodium 2-ethylhexyl sulfate
4-Methyl-5-nonanone
p-Toluoyl chloride
1-Fluorodecane
2,4,6-Trimethylphenylisothiocyanate
2-Methylbenzoyl chloride
Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate
Tris(2-ethylhexyl) phosphate
3-Isopropylphenylboronic acid
1-Methyl-1H-imidazole-2-thiol
4-Heptylbenzoic acid
4-Isopropylphenylboronic acid
4-Pentyl-1,1-Biphenyl
2,4,6-Trimethylstyrene
(4-Chloro-3-(isopropylcarbamoyl)phenyl)boronic acid
4'-Heptyl-[1,1'-biphenyl]-4-carbonitrile
2,6-Di-tert-butyl-4-ethylphenol
(E)-2-Ethylhexyl 3-(4-methoxyphenyl)acrylate
(3-(N-Isopropyl-N-(4-methoxybenzyl)sulfamoyl)phenyl)boronic acid
(4-(Diisopropylcarbamoyl)phenyl)boronic acid
Dichlorobis(2-ethylhexyl)silane
5-Propyldihydrofuran-2(3H)-one
(S)-3-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-4-(4-(tert-butyl)phenyl)butanoic acid
4-Bromo-2-hydroxy-6-methylbenzaldehyde
1-((2-Ethylhexyl)oxy)-4-methoxybenzene
(4-((2,6-Diisopropylphenoxy)methyl)phenyl)boronic acid
