Intermediates refer to semi-finished products, which are intermediate products for the production of certain products, such as the production of a product that can be produced from intermediates and save costs.

The intermediates are formed by reactions such as sulfonation, alkali fusion, nitration and reduction of cyclic compounds such as benzene, naphthalene, anthraquinone, and the like. For example, benzene is nitrated to nitrobenzene and then reduced to aniline. Aniline can be chemically processed into dyes, drugs, vulcanization accelerators, and the like. Both nitrobenzene and aniline are intermediates.

There are also acyclic compounds such as methane, acetylene, propylene, butane, butene, etc. which are dehydrogenated, polymerized, halogenated, and hydrolyzed. For example, butane or butene can be dehydrogenated to butadiene, and butadiene can be chemically processed into synthetic rubber, synthetic fibers, and the like. Butadiene is an intermediate.

Initially, it refers to intermediate products produced during the process of synthesizing chemical products such as perfumes, dyes, resins, drugs, plasticizers, and rubber accelerators using coal tar or petroleum products as raw materials. Now refers to the various intermediate products obtained during organic synthesis.