55-21-0 Usage
Safety Profile
Moderately toxic by ingestion andintraperitoneal routes. When heated to decomposition itemits toxic fumes of NOx.
Description
Benzamide appears as off-white crystals or powder. It is combustible and incompatible with strong oxidising agents and strong bases. On combustion and thermal decomposition, it emits nitrogen oxides, carbon monoxide, and carbon dioxide.
Benzamide is a carbonic acid amide of benzoic acid. Benzamide exhibits an angle of about 15o with the plane of the amide group; this shows that benzamide molecule is not flat. The rotation of the amide group relative to the aromatic ring may result from the repulsion interaction between the hydrogen atoms of the amide group and those of the aromatic ring.
Chemical Properties
Benzamide is a combustible, colorless to beige, off-white, crystalline solid; freezing/melting point=132-133° C. It is slightly soluble in water, and soluble in many organic solvents.
Benzamide was used to study the mechanism of photocatalytic decomposition of aqueous solution of acetic acid, acetamide and acetonitrile in the presence of semiconductors. It was used to develop a robust screening method to study biotransformations using (+)-γ-lactamase enzyme.
Uses
Different sources of media describe the Uses of 55-21-0 differently. You can refer to the following data:
1. Organic synthesis.Benzamide on radioiodination by different labeling procedures results in large-scale production of radioiodinated benzamides having potential therapeutic application for patients with metastatic malignant melanoma.
2. Benzamide is utilized to study the mechanism of photocatalytic decomposition of aqueous solution of acetic acid, acetamide and acetonitrile in the presence of semiconductors. It is used as a nictoinamide-mimic PARP inhibitor and neuroprotectant. Further, it is used to develop a robust screening method to study biotransformations using (+)-gamma-lactamase enzyme. It is also employed in the determination of glycine. In addition to this, it is used as an intermediate in organic synthesis as well as in the production of pharmaceuticals and dyes.
Preparation
Take a mixture of 5 ml concentrated ammonia and 5 ml water in a conical flask with a well-fitting cork. Add 2 ml (2.4 g.) benzoyl chloride, cork the flask and shake vigorously. Heat generates due to the reaction, hence hold the cork securely during shaking. After 15 min not even a trace of oily benzoyl chloride remains. Filter the fine flakes, wash with cold water and recrystallise from hot water: yield, 1-5 g. Colourless crystals of benzamide.
Preparation of benzamide from benzoyl chloride
Definition
ChEBI: An aromatic amide that consists of benzene bearing a single carboxamido substituent. The parent of the class of benzamides.
Synthesis Reference(s)
The Journal of Organic Chemistry, 59, p. 4114, 1994 DOI: 10.1021/jo00094a021Chemical and Pharmaceutical Bulletin, 39, p. 1152, 1991 DOI: 10.1248/cpb.39.1152Synthetic Communications, 20, p. 1445, 1990 DOI: 10.1080/00397919008052860
Reactivity Profile
Benzamide reacts with azo and diazo compounds to generate toxic gases. Forms flammable gases with strong reducing agents. Mixing with dehydrating agents such as P2O5 or SOCl2 generates the corresponding nitrile. Combustion generates toxic mixed oxides of nitrogen (NOx).
Hazard
Depresses the central nervous system;
toxic.
Fire Hazard
Flash point data for Benzamide are not available, however Benzamide is probably combustible.
Biochem/physiol Actions
Inhibits poly(ADP-ribose) polymerase (PARP).
Clinical Use
Benzamide on radioiodination by different labeling procedures results in large-scale production of radioiodinated benzamides having potential therapeutic application for patients with metastatic malignant melanoma.
Potential Exposure
Benzamide is used in organic
synthesis.
Purification Methods
Crystallise it from hot water (about 5mL/g), EtOH or 1,2-dichloroethane, and dry it in air. It has also been crystallised from dilute aqueous NH3, H2O, Me2CO, then *C6H6 using a Soxhlet extractor. Dry it in an oven at 110o for 8hours and store in a desiccator over 99% H2SO4. [Bates & Hobbs J Am Chem Soc 73 2151 1951, Beilstein 9 IV 725.]
Check Digit Verification of cas no
The CAS Registry Mumber 55-21-0 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 5 and 5 respectively; the second part has 2 digits, 2 and 1 respectively.
Calculate Digit Verification of CAS Registry Number 55-21:
(4*5)+(3*5)+(2*2)+(1*1)=40
40 % 10 = 0
So 55-21-0 is a valid CAS Registry Number.
InChI:InChI=1/C7H7NO/c8-7(9)6-4-2-1-3-5-6/h1-5H,(H2,8,9)
55-21-0Relevant articles and documents
Nitrogen Atom Transfer Catalysis by Metallonitrene C?H Insertion: Photocatalytic Amidation of Aldehydes
Schmidt-R?ntsch, Till,Verplancke, Hendrik,Lienert, Jonas N.,Demeshko, Serhiy,Otte, Matthias,Van Trieste, Gerard P.,Reid, Kaleb A.,Reibenspies, Joseph H.,Powers, David C.,Holthausen, Max C.,Schneider, Sven
supporting information, (2022/01/20)
C?H amination and amidation by catalytic nitrene transfer are well-established and typically proceed via electrophilic attack of nitrenoid intermediates. In contrast, the insertion of (formal) terminal nitride ligands into C?H bonds is much less developed and catalytic nitrogen atom transfer remains unknown. We here report the synthesis of a formal terminal nitride complex of palladium. Photocrystallographic, magnetic, and computational characterization support the assignment as an authentic metallonitrene (Pd?N) with a diradical nitrogen ligand that is singly bonded to PdII. Despite the subvalent nitrene character, selective C?H insertion with aldehydes follows nucleophilic selectivity. Transamidation of the benzamide product is enabled by reaction with N3SiMe3. Based on these results, a photocatalytic protocol for aldehyde C?H trimethylsilylamidation was developed that exhibits inverted, nucleophilic selectivity as compared to typical nitrene transfer catalysis. This first example of catalytic C?H nitrogen atom transfer offers facile access to primary amides after deprotection.
Cu(II)-promoted oxidative C-N bond cleavage of N-benzoylamino acids to primary aryl amides
Zhou, Liandi,Liu, Wei,Zhao, Yongli,Chen, Junmin
, p. 52 - 62 (2021/02/06)
A novel protocol for CuCl2-promoted oxidative C-N bond cleavage of N-benzoyl amino acids was developed. It is the first example of using accessible amino acid as an ammonia synthetic equivalent for the synthesis of primary aryl amides via CuCl2-promoted oxidative C-N bond cleavage reaction. The present protocol shows excellent functional group tolerance and provides an alternative method for the synthetic of primary aryl amides in 84-96% yields.
Gram-Scale Preparation of Acyl Fluorides and Their Reactions with Hindered Nucleophiles
Barbasiewicz, Micha?,Tryniszewski, Micha?
, (2021/11/30)
A series of acyl fluorides was synthesized at 100 mmol scale using phase-transfer-catalyzed halogen exchange between acyl chlorides and aqueous bifluoride solution. The convenient procedure consists of vigorous stirring of the biphasic mixture at room temperature, followed by extraction and distillation. Isolated acyl fluorides (usually 7-20 g) display excellent purity and can be transformed into sterically hindered amides and esters when treated with lithium amide bases and alkoxides under mild conditions.