103-26-4

Chemical Properties

Methyl cinnamate appears as white to slightly yellow crystals with a cherry and balsamic aroma. Melting point 34 ℃. The boiling point is 260°C, and the refractive index (nD20) is 1.5670. Relative density (d435) 1.0700. Soluble in alcohol, ether, glycerin, propylene glycol, most non-volatile oils and mineral oils, insoluble in water.Natural products are contained in basil oil (up to 52%), galangal oil and bay leaf oil.

Preparative Methods

It is obtained by esterification of cinnamic acid with methanol. The mixture of cinnamic acid, methanol and sulfuric acid (or hydrochloric acid) was heated to reflux for 5 h, and the excess amount of methanol was added. Cool and spate the acid layer, washed with water and 10% sodium carbonate solution, and then washed with water to neutral. The crude product was subjected to recrystallization or vacuum distillation [collection of 132-134 ° C (2.0 kPa) fraction] to give methyl cinnamate with a yield of about 70%.

Description

Methyl cinnamate is the methyl ester of cinnamic acid and is a white or transparent solid with a strong, aromatic odor. It is found naturally in a variety of plants, including in fruits, like strawberry, and some culinary spices, such as Sichuan pepper and some varieties of basil. Eucalyptus olida has the highest known concentrations of methyl cinnamate (98 %) with a 2 - 6 % fresh weight yield in the leaf and twigs. Methyl cinnamate is used in the flavor and perfume industries. The flavor is fruity and strawberry-like; and the odor is sweet, balsamic with fruity odor, reminiscent of cinnamon and strawberry. It is known to attract males of various orchid bees, such as Aglae caerulea. Methyl cinnamate crystals extracted using steam distillation from Eucalyptus olida.

Occurrence

Reported found in the oil from rhizomes of Alpinia malaccensis, in the oil from leaves of Ocimum canum Sims.; in the oil of Narcissus jonquilla L.; in the oil from rhizomes of Gastrochilus panduratum Ridl.; two isomers (cis- and trans-) exist in natural. Also reported found in cranberry, guava, pineapple, strawberry fruit and jam, cinnamon leaf, Camembert cheeses, cocoa, avocado, plum, prune, cloudberry, starfruit, plum brandy, rhubarb, beli (Aegle marmelos Correa), loquat and Bourbon vanilla.

Uses

Methyl cinnamate is used as a fragrance ingredient in cosmetics and household products.

Preparation

Methyl cinnamate is synthesized by esterification of cinnamic acid with methanol using HCl as catalyst, or by adding HCl to a boiling solution of cinnamyl nitrile in methanol.

Synthesis Reference(s)

Journal of the American Chemical Society, 96, p. 1133, 1974 DOI: 10.1021/ja00811a029Tetrahedron Letters, 29, p. 6119, 1988 DOI: 10.1016/S0040-4039(00)82281-9

General Description

Methyl cinnamate is an important flavoring agent and fragrance ingredient. It is one of the main aroma components of basil oil, Japanese and Korean matsutake mushrooms.

Flammability and Explosibility

Nonflammable

Safety Profile

Moderately toxic by ingestion. Combustible liquid. When heated to decomposition it emits acrid smoke and irritating fumes.

Who Evaluation

Evaluation year: 2000