1-Naphthyl acetonitrile
[CAS# 132-75-2]

Identification

• Classification: Organic raw materials >> Nitrile compound
• Name: 1-Naphthyl acetonitrile
• Synonyms: a-Naphthylacetonitrile; 1-Naphthylacetonitrile
• Molecular Formula: C₁₂H₉N
• Molecular Weight: 167.21
• CAS Registry Number: 132-75-2
• EC Number: 205-078-1
• SMILES: C1=CC=C2C(=C1)C=CC=C2CC#N

Properties

• Density: 1.1±0.1 g/cm³ Calc.^*
• Melting point: 33 - 35 ºC (Expl.)
• Boiling point: 323.9 ºC 760 mmHg (Calc.)^*, 365.1 - 367.9 ºC (Expl.)
• Flash point: 180.3±5.7 ºC (Calc.)^*, 113 ºC (Expl.)
• Index of refraction: 1.634 (Calc.)^*, 1.619 (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H302-H312-H315-H319-H332-H335
• Precautionary Statements: P261-P264-P264+P265-P270-P271-P280-P301+P317-P302+P352-P304+P340-P305+P351+P338-P317-P319-P321-P330-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H332
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2	H319
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	3	H331
Acute toxicity	Acute Tox.	3	H311
Acute toxicity	Acute Tox.	3	H301
Eye irritation	Eye Irrit.	2A	H319

Discovory and Applicatios

1-Naphthyl acetonitrile is an aromatic organic compound consisting of a naphthalene ring substituted at the 1-position with an acetonitrile group (-CH₂CN). Its molecular formula is C₁₂H₉N, and it is structurally related to other naphthalene derivatives used as intermediates in pharmaceuticals, agrochemicals, and specialty chemicals.

The synthesis of 1-naphthyl acetonitrile typically involves the alkylation of 1-bromonaphthalene with a cyanomethyl anion equivalent, or the reaction of 1-naphthaldehyde with hydroxylamine to form the oxime followed by dehydration and rearrangement to introduce the nitrile functionality. Other synthetic approaches include nucleophilic substitution using 1-naphthylmethyl halides and alkali metal cyanides under appropriate conditions. These methods enable efficient access to the desired α-aryl nitrile compound with high yields.

The nitrile group in 1-naphthyl acetonitrile is both polar and reactive, serving as a key handle for further functionalization. It can undergo hydrolysis to yield carboxylic acids, reduction to primary amines, or participate in condensation reactions for heterocycle formation. This versatility makes the compound valuable in synthetic chemistry, particularly in the construction of pharmacophores or ligands.

In pharmaceutical development, arylacetonitriles such as 1-naphthyl acetonitrile are considered useful scaffolds due to their stability and ability to participate in various biological interactions. The rigid naphthalene system provides hydrophobic surface area and potential π-π stacking capabilities, often contributing to binding affinity in enzyme or receptor studies.

Physically, 1-naphthyl acetonitrile is usually a solid at room temperature, appearing as a white to light yellow crystalline material. It is soluble in common organic solvents such as ethanol, acetone, and dichloromethane but only sparingly soluble in water. It has a characteristic aromatic odor and must be handled with care due to the reactivity of the nitrile group under strong acidic or basic conditions.

Spectroscopic identification is supported by infrared absorption bands for the nitrile stretch (around 2220 cm^-1), and distinctive aromatic proton signals in ¹H NMR. Mass spectrometry confirms its molecular weight and fragmentation consistent with loss of the -CN group or cleavage of the methylene bridge.

While 1-naphthyl acetonitrile is not widely used as a final product, its role as a synthetic intermediate is well established in the preparation of more complex structures such as dyes, fluorescent labels, or biologically active compounds. Its stability and defined reactivity make it a practical compound in research and development environments.

In summary, 1-naphthyl acetonitrile is a nitrile-substituted naphthalene compound valued for its reactivity and role as an intermediate in synthetic organic chemistry. Its structure supports a wide range of chemical transformations, making it useful in the design and construction of advanced aromatic compounds.

References

2008. Hydrotalcite-bound ruthenium as a multifunctional heterogeneous catalyst for one-pot synthesis of α-alkylated nitriles and quinolines. Research on Chemical Intermediates, 34(5).
DOI: 10.1163/156856708784795554

2001. Fragmentation of Anion Radicals with Elimination of Aryloxy Groups. Russian Journal of Organic Chemistry, 37(10).
DOI: 10.1023/a:1013456112725

2012. Decarboxylative Coupling with Cyanoacetate Metal Salts. Science of Synthesis.
URL: https://science-of-synthesis.thieme.com/app/text/?id=SD-208-00413