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Updated: Jun 5, 2026
11:01
Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
2,2-Dichloro-N-(2,3-dimethyl-phen-yl)acetamide.
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
The N-H bond conformation in C(10)H(11)Cl(2)NO is syn to methyl groups, differing from some related acetanilides. Molecules form chains via N-H⋯O and C-H⋯O hydrogen bonding.
Area of Science:
- Organic Chemistry
- Crystallography
Background:
- Acetanilides are a significant class of organic compounds with diverse applications.
- Understanding the conformational preferences and intermolecular interactions of substituted acetanilides is crucial for predicting their properties and designing new molecules.
Purpose of the Study:
- To determine the molecular conformation and hydrogen bonding patterns of a novel dichloro-substituted acetanilide derivative, C(10)H(11)Cl(2)NO.
- To compare the observed conformation with related acetanilide structures.
Main Methods:
- Single-crystal X-ray diffraction was employed to analyze the crystal structure of C(10)H(11)Cl(2)NO.
- Analysis of bond parameters and intermolecular interactions, including hydrogen bonds.
Main Results:
- The N-H bond in C(10)H(11)Cl(2)NO adopts a syn conformation relative to the 2- and 3-methyl substituents on the aromatic ring.
- This conformation contrasts with the anti conformation observed for the 3-methyl substituent in a related compound.
- Molecular packing reveals the formation of chains through N-H⋯O and C-H⋯O hydrogen bonding.
Conclusions:
- The study elucidates the specific conformational behavior of the N-H bond in the title compound, influenced by adjacent methyl groups.
- The identified hydrogen bonding network highlights the intermolecular forces governing the crystal structure of this acetanilide derivative.
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Naming Amides
The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.
The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.
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Carboxylic acids react with diazomethane in an ether solvent via alkylation at the carboxylate oxygen atom to give methyl esters of the corresponding acid with excellent yields.
01:19Diazonium Group Substitution: –OH and –H
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
01:19Amines to Amides: Acylation of Amines
Various carboxylic acid derivatives (such as acid chlorides, esters, and anhydrides) can be used for the acylation of amines to yield amides. The reaction requires two equivalents of amines. The first amine molecule functions as a nucleophile and attacks the carbonyl carbon to produce a tetrahedral intermediate. This is followed by the loss of the leaving group and restoration of the C=O bond.
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Structure of Carboxylic Acid Derivatives
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