Quaternary is a term used in organic chemistry to classify various types of compounds (e. g. amines and ammonium salts).Paula Yurkanis Bruice: Organic Chemistry, Pearson Education Inc., 2004, 4. Ed., p. 78, 104, 893, and 912, .
Red highlighted central atoms in various groups of chemical compounds. Quaternary central atoms compared with primary, secondary and tertiary central atoms. primary secondary tertiary quaternary Carbon atom in an alkane Alcohol does not exist Amine Amide does not exist Phosphine
See also Primary (chemistry) Secondary (chemistry) Tertiary (chemistry)
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