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7.9: Nitriles, RCN

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    22199
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    1. Compounds with the \(\equiv N\) function are named by adding the suffix nitrile to the main-chain hydrocarbon that includes the carbon linked to the nitrile (\(\equiv N\)) function. The chain is numbered so the \(CN\) carbon is \(C1\):

    Left: C H 3 C N; labeled ethanenitrile (acetonitrile). Middle: C H 3 C H double bond C H single bond C H (with C H 3 substituent) single bond C H double bond C H C triple bond N. Labeled 4-methyl-2,5-heptadienenitrile. Right: N C C H 2 C H 2 C H 2 C N. Labeled pentanedinitrile.

    2. Compounds of the type \(RCN\) have to be called carbonitriles when \(R\) is a cycloalkane or similar group:

    Left: cyclohexane with a C N substituent; labeled cyclohexanecarbonitrile. Right: benzene ring with C N substituents on carbons 1 and 4. Labeled 1,4-benzenedicarbonitrile.

    3. Nitriles can be regarded as derivatives of carboxylic acids because the acid, \(RCO_2H\), usually can be obtained from the nitrile, \(RCN\):

    R C triple bond N labeled nitrile. Arrow with H 2 O goes to R C double bond O single bond N H 2 labeled amide. Arrow with H 2 O minus N H 3 goes to R single bond C with a double bond O and single bond O H. Labeled acid.

    A common system of naming nitriles takes the name of the corresponding carboxylic acid and changes the suffix -oic to -onitrile:

    Benzene ring with a C triple bond N substituent labeled benzonitrile. Arrow with H 2 O goes to benzene with C with a double bond O and single bond N H 2 substituent. Labeled benzamide. Arrow with H 2 O goes to benzene with a C with a double bond O and a single bond O H labeled benzoic acid.

    4. The substituent name for \(-CN\) is cyano. For example,

    Left: C H 2 C H 2 C O 2 H with benzene ring with C N on carbon 3 on carbon 3. Labeled 3-(3-cyanophenyl) propanoic acid. Right: C H 3 single bond C with a double bond O and single bond O C H 3 C N. Labeled cyanomethyl ethanoate.

    Contributors and Attributions

    John D. Robert and Marjorie C. Caserio (1977) Basic Principles of Organic Chemistry, second edition. W. A. Benjamin, Inc. , Menlo Park, CA. ISBN 0-8053-8329-8. This content is copyrighted under the following conditions, "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format."


    This page titled 7.9: Nitriles, RCN is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by John D. Roberts and Marjorie C. Caserio.