Aldehydes, Ketones, and their Derivatives

Acyclic Aldehydes Rule C-303

303.1 - (a) The name of an acyclic polyaldehyde in which more than two aldehyde groups are attached to an unbranched chain is formed by adding "-tricarbaldehyde", "-tetracarbaldehyde", etc., to the name of the longest chain carrying the maximum number of aldehyde groups. The name and numbering of the main chain do not include the aldehyde groups, and numbering follows the general principles for unsaturation and substituents. (b) Alternatively, the name is formed by adding the prefix "formyl-" to the name of the dial incorporating the principal chain.

Examples to Rule C-303.1

303.2 - An aldehyde group in an acyclic compound is named by the prefix "formyl-" when a group having priority for citation as principal group is also present. (See, however, also Rules C-415, and C-416.)

Example to Rule C-303.2

303.3 - For an acyclic polyaldehyde, in which the aldehyde groups -CHO are attached to more than one branch of a branched chain, the name of the longest chain carrying the greatest number of aldehyde groups is used together with a suffix "-dial" (see Rule C-302.1), "-tricarbaldehyde", etc. (see Rule C-303.1), and other chains carrying aldehyde groups are named by use of "formylalkyl-" prefixes.

Examples to Rule C-303.3

See Recommendations'93 R-5.6.1

Aldehydes Rule C-304, Rule C-305
Ketones Rule C-311, Rule C-312, Rule C-313, Rule C-314 , Rule C-315, Rule C-316, Rule C-317, Rule C-318
Ketenes Rule C-321
Acetals and Acylals Rule C-331, Rule C-332, Rule C-333


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