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Alcohols, Phenols, and their Derivatives

Ethers Rule C-212

212.1 - Oxygen linking two identical parent compounds may be indicated by the prefix "oxy" when a group having priority for citation as suffix is present, the nomenclature for assemblies of identical units (compare Subsection C-0.7) being used.

Examples to Rule C-212.1

212.2 - An oxygen atom directly attached to two carbon atoms already forming part of a ring system or to two carbon atoms of a chain may be indicated by the prefix "epoxy-", particularly when it is desired to preserve the name of a specific complex structure, as, for example, steroids or carotenoids. (see also Rule B-15).

Examples to Rule C-212.2

[see Rule C-16.11(examples), (a) (viii)]
or 1,3-Epoxy-2-methylhexane
[see Rule C-16.11(examples), (b) (ii) ]

[Note: epoxy is not alphabetized;
see Rule C-16.11(examples), (a) (viii)].

212.3 - Compounds RO-X-OR, where the two parent compounds RH are identical and contain a group having priority over ether for citation as suffix, and -X- is any bivalent radical, are named by the method for assemblies of identical units (Subsection C-0.7).

Example to Rule C-212.3

212.4 - Linear polyethers derived from three or more molecules of aliphatic dihydroxy compounds are most conveniently named by the openchain replacement nomenclature (see Subsection C-0.6).

Examples to Rule C-212.4

212.5 - Symmetrical linear polyethers may be named in terms of the central oxygen atom when there is an odd number of ether oxygen atoms. or in terms of the central hydrocarbon group when there is an even number of ether oxygen atoms.

Examples to Rule C-212.5

See Recommendations'93 R-5.5.4

Ethers Rule C-213, Rule C-214, Rule C-215, Rule C-216
Peroxides Rule C-218

This HTML reproduction of Sections A, B and C of IUPAC "Blue Book" is as close as possible to the published version [see Nomenclature of Organic Chemistry, Sections A, B, C, D, E, F, and H, Pergamon Press, Oxford, 1979. Copyright 1979 IUPAC.] If you need to cite these rules please quote this reference as their source.

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