Preferred Label : tautomerism;
IUPAC definition : isomerism of the general form: where the isomers (called tautomers) are readily interconvertible;
the atoms connecting the groups X, Y, Z are typically any of C, H, O or S, and G is
a group which becomes an electrofuge or nucleofuge during isomerization. The commonest
case, when the electrofuge is H sup class plus /sup , is also known as 'prototropy'.
Examples, written so as to illustrate the general pattern given above, include: keto-enol
tautomerism, such as: The grouping Y may itself be a three-atom (or five-atom) chain
extending the conjugation, as in: The double bond between Y and Z may be replaced
by a ring, when the phenomenon is called ring-chain tautomerism, as in:;
Origin ID : T06252;
See also
isomerism of the general form: where the isomers (called tautomers) are readily interconvertible;
the atoms connecting the groups X, Y, Z are typically any of C, H, O or S, and G is
a group which becomes an electrofuge or nucleofuge during isomerization. The commonest
case, when the electrofuge is H sup class plus /sup , is also known as 'prototropy'.
Examples, written so as to illustrate the general pattern given above, include: keto-enol
tautomerism, such as: The grouping Y may itself be a three-atom (or five-atom) chain
extending the conjugation, as in: The double bond between Y and Z may be replaced
by a ring, when the phenomenon is called ring-chain tautomerism, as in:
