Cyanoacetic acid

Description

Cyanoacetic acid is an organic compound. It is a white, hygroscopic solid. The compound contains two functional groups, a nitrile (C≡N) and a carboxylic acid. It is a precursor to cyanoacrylates, components of adhesives.
Cyanoacetic acid is used in pharmaceutical industry for producing vitamin B6 and caffeine. It is also used in making dyes, agricultural chemicals, and in the synthesis of phenylacetic acid esters. It acts as a precursor cyanoacrylates viz. ethyl cyanoacrylate.

Chemical Properties

white to light beige adhering crystalline solid

Uses

Cyanoacetic acid was used in the synthesis of N-piperidine-cyanacetamide and N-morpholyl-cyanacetamide. It was also used in the preparation of a panchromatic dye for dye-sensitized solar cells.

Uses

Cyanoacetic acid is used in pharmaceutical industry for producing vitamin B6 and caffeine. It is also used in making dyes, agricultural chemicals, and in the synthesis of phenylacetic acid esters. It acts as a precursor cyanoacrylates viz. ethyl cyanoacrylate.

Uses

Synthesis of intermediates; manufacture of barbital.

Definition

ChEBI: A monocarboxylic acid that consists of acetic acid bearing a cyano substituent.

Application

Cyanoacetic acid can be used as a reagent:
Along with acetic anhydride for cyanoacetylation of various pyrroles, indoles, and aniline derivatives. It can also be used in other reactions such as cyclizations, syntheses of coumarins and other heterocycles.
To prepare of key intermediate via Knoevenagel condensation in the total synthesis of 5-acetamido-substituted melatonin derivatives as MT3 receptor ligands.
In the synthesis of aminopyrrolinone derivatives by reacting Ugi adducts of cyanoacetic acid and aromatic aldehydes.

Preparation

Cyanoacetic acid is prepared by treatment of chloroacetate salts with sodium cyanide followed by acidification. Electrosynthesis by cathodic reduction of carbon dioxide and anodic oxidation of acetonitrile also affords cyanoacetic acid.

General Description

Yellow-brown liquid with an unpleasant odor. Sinks and mixes with water.

Air & Water Reactions

Water soluble.

Reactivity Profile

White, moderately toxic solid, combustible. When heated to decomposition Cyanoacetic acid emits toxic fumes of nitrile and oxides of nitrogen. A stirred mixture with furfuryl alcohol exploded violently upon heating [MCA Case History No 858].

Health Hazard

Contact irritates eyes and may irritate skin.

Fire Hazard

Special Hazards of Combustion Products: Toxic oxides of nitrogen and toxic and flammable acetonitrile vapors may form in fire.

Purification Methods

Recrystallise the acid to constant melting point from *benzene/acetone (2:3), and dry it over silica gel. [Beilstein 2 H 583, 2 I 253, 2 II 530, 2 III 1626, 2 IV 1888.]