Term: quasi-enantiomers
https://doi.org/10.1351/goldbook.Q04997

Definition:
Constitutionally different yet closely related chemical species MX and MY having the opposite chirality sense of the large common chiral moiety M. For example (R)-2-bromobutane is a quasi-enantiomer of (S)-2-chlorobutane.

Related Terms:
1) quasi-racemic compound (http://doi.org/10.1351/goldbook.Q05001).
2) chirality sense (http://doi.org/10.1351/goldbook.C01063).
3) chiral (http://doi.org/10.1351/goldbook.C01057).
4) moiety (http://doi.org/10.1351/goldbook.M03968).
5) enantiomer (http://doi.org/10.1351/goldbook.E02069).

Source: PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2215 (https://doi.org/10.1351/pac199668122193)

Citation: 'quasi-enantiomers' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.Q04997

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