Organotin Compounds (redirected from Organotin)

Organotin Compounds 

a class of organometallic compounds containing at least one C—Sn bond per molecule. Almost all known organotin compounds are formed from tetravalent tin; they include fully substituted R₄Sn compounds, as well as compounds of the formulas R₃SnX, R₂SnX₂, and RSnX3, where R represents identical or different organic radicals and X denotes a halogen, hydrogen, oxygen, or a radical bonded to the tin atom by a heteroatom of oxygen, nitrogen, sulfur, and so on: for example,—OCH₃,—NHCH₃,—OH, and—SR. Thus, the main organotin compounds containing oxygen are hydroxides, R₃SnOH; oxides, R₃SnOSnR₃ and R₂SnO; and stannous acids, RSnOOH. The molecules of certain organotin compounds form linear chains or rings of tin atoms containing side organic radicals.

Most organotin compounds have low-polarity Sn—C and Sn—X bonds. The Sn—C bond is less reactive than the tinheteroatom bond; it is resistant to the effects of water and atmospheric oxygen but breaks upon action of halogens and acids. A characteristic feature of organotin hydrides, R_nSnH_{4 – n}, is the ability to join to various multiple bonds. The physical properties of organotin compounds vary considerably, ranging from highly volatile liquids that are readily soluble in organic solvents to infusible and insoluble substances. Organotin compounds containing heteroatoms are often associated in solutions and crystals or exhibit polymeric structure.

Compounds of the R₄Sn type are usually produced upon interaction of stannic chloride with organic compounds of lithium, magnesium, or aluminum, as well as by treating tin alloys containing sodium or magnesium with alkyl halides. Organotin halides are the starting materials for the preparation of various organotin compounds, which are formed by reaction of R₄Sn with tin halides or with halogens or reaction of metallic tin with alkyl halides. Certain organotin compounds are toxic.

Compounds of the formulas R₃SnX and R₂SnX₂ are widely used as stabilizers for polyvinyl chloride resins (for example, dibutyltin dilaurate), fungicides (triphenyltin acetate), and bactericides (tributyltin benzoate).

REFERENCE

Metody elementoorganicheskoi khimii. Moscow, 1968.

D. N. KRAVTSOV