Benzaldehyde, C 6 H 5 CHO, is the simplest and possibly the most industrially useful member of the family of aromatic aldehydes. Benzaldehyde exists in nature, primarily in combined forms such as a glycoside in almond, apricot, cherry, and peach seeds. The characteristic benzaldehyde odor of oil of bitter almond occurs because of trace amounts of free benzaldehyde formed by hydrolysis of the glycoside amygdalin. Benzaldehyde is a versatile intermediate because of its reactive aldehyde hydrogen, its carbonyl group, and the benzene ring. The only industrially important processes for the manufacturing of synthetic benzaldehyde involve the hydrolysis of benzal chloride and the air oxidation of toluene. The hydrolysis of benzal chloride is no longer utilized in the United States. Benzaldehyde is produced in the United States by Kalama Chemical Incorporated, Kalama, Washington. Benzaldehyde is sold as technical grade or as meeting the specifications of the National Formulary (NF), the Food Chemicals Codex (FCC), or the British Pharmacopeia (BP). The oral LD 50 for benzaldehyde is reported as 1300 mg/kg in rats and as 1000 mg/kg in guinea pigs. Based upon these values, benzaldehyde is considered a moderately toxic substance when ingested. Overexposure to benzaldehyde vapors is irritating to the upper respiratory tract and produces central nervous system depression, with respiratory failure possible. The low autoignition temperature of benzaldehyde (192°) presents safety problems. Benzaldehyde may also spontaneously ignite when soaked into rags or clothing or adsorbed onto activated carbon. Bulk storage of benzaldehyde should be made under a nitrogen blanket. Benzaldehyde is a synthetic flavoring substance, sanctioned by the U.S. Food and Drug Administration (FDA) to be generally recognized as safe (GRAS) for foods. Both “pure almond extract” and “imitation almond extract” are offered for sale; each contains 2.0–2.5 wt % benzaldehyde. Benzaldehyde is also recognized as safe for use as a bee repellant in the harvesting of honey. Benzaldehyde's most important use is in organic synthesis, where it is the raw material utilized to produce various aldehydes.

Benzaldehyde is the simplest and quite possibly the most industrially useful aromatic aldehyde. It is manufactured from toluene, either by chlorination, followed by hydrolysis, or by liquid phase air oxidation. The air oxidation of toluene to produce benzoic acid is the source of most of the world's synthetic benzaldehyde. Benzaldehyde is widely used directly, as a synthetic flavoring substance, or as a raw material in the synthesis of industrially important derivatives such as benzyl alcohol, benzoin and benzil and several benzyl amines. The hydrogenation of benzaldehyde to form benzyl alcohol is the largest single use of benzaldehyde. In addition, benzaldehyde serves as the major raw material a wide variety of fragrance compounds are derivatives of benzaldehyde. The major products in the fragrance category are cinnamic aldehyde and a number of substituted cinnamic aldehydes; such as methyl, butyl, amyl, and hexyl cinnamic aldehydes.

The simplest member of the aromatic carboxylic acid family, benzoic acid was first described in the 17 th century and initially used extensively as a medicinal substance. Currently the main uses for benzoic acid are as a chemical additive in alkyd resins and as a raw material in the manufacture of phenol, caprolactam, glycol dibenzoate plasticizer esters, and in the production of the food preservatives, sodium and potassium benzoates. The liquid phase air oxidation of toluene provides most of the world's supply of benzoic acid. Large quantities of benzaldehyde can be recovered in the same process. Other major derivatives of benzoic acid include benzoyl chloride, benzoic anhydride, and a number of benzyl esters, used in fragrances and personal care products. These include methyl, ethyl, butyl and hexyl benzoate as well as alkyl (C12‐15) benzoate.

Benzoic acid, C 6 H 5 COOH, is the simplest member of the aromatic carboxylic acid family. In the United States, virtually all benzoic acid is manufactured by the continuous liquid‐phase air oxidation of toluene. Benzoic acid and its salts and esters find application in medicinals, food and industrial preservatives, cosmetics, resins, plasticizers, dyestuffs, and fibers. Benzoic acid in the free state, or in the form of simple derivatives such as salts, esters, and amides, is widely distributed in nature. In its chemical behavior benzoic acid shows few exceptional properties; the reactions of the carboxyl group are normal, and ring substitutions take place as would be predicted. The growth of demand for benzoic acid is expected to increase at a rate of between 1 and 2% per year. Glycol dibenzoate plasticizers have been growing at close to 10% annually for several years, in part due to environmental concerns with regard to phthalate plasticizers. The growth of the diet soft drink market has increased the demand for sodium and potassium benzoates. All of the benzoic acid producers in the United States employ the liquid‐phase toluene air oxidation process. The bulk of benzoic acid production capacity is consumed internally by the producers. Kalama converts over half of its production to phenol. A large portion of Velsicol's benzoic acid production is utilized in the manufacture of glycol dibenzoate plasticizer esters. Benzoic acid is available in industrial and technical grades, and in grades meeting the specifications of the United States Pharmacopeia , the Food Chemicals Codex , or the British Pharmacopeia . Benzoic acid's toxicity is rated as moderate (3 on a scale of 1–6). Healthy individuals may tolerate small doses (under 0.5 g of benzoates per day) mixed with food without ill effects. The principal safety concern in handling molten benzoic acid is its elevated temperature. Thermal burns may result from improper handling of the molten product. Benzoic acid derivatives include benzoyl chloride (C 6 H 5 COCl), benzoic anhydride ((C 6 H 5 CO) 2 O), benzoic acid salts, and benzoic acid esters.