alpha carbon

The alpha carbon in organic chemistry refers to the first carbon after the carbon that attaches to the functional group (the carbon is attached at the first, or alpha, position). By extension, the second carbon is the beta carbon, and so on. This nomenclature can also be applied to the hydrogen atoms attached to the carbons. A hydrogen attached to an alpha carbon is called an "alpha-hydrogen" (α-hydrogen), a hydrogen on the beta-carbon is a beta-hydrogen, and so on.
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