Preparation of organotin compounds

Among organotin compounds the most widely used are various organic salts of dialkyl tin, such as diethyl- and di-n-butyltin dicaprylates, di-n-butyltin dilaurate, di-n-butyltin distearate, etc. As a rule, these compounds are obtained through tin alkylhalogenides. 

Tin alkylhalogenides can be prepared by several techniques, the most important of which are direct synthesis and organomagnesium synthesis. 

Direct synthesis is based on the interaction of alkylhalogenide with tin oxide. 

This technique is of practical interest first and foremost for the synthesis of tin methylhalogenides since no suitable conditions have yet been found for the production of higher alkylhalogenides with any significant yield. 

The raw stock for direct synthesis can be both tin oxide and metallic tin. 3Sn + 6RHaI----------- RSnHaI3 + R2SnHaI2 + R3SnHaI (5.43) 

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There are a number of reports of the preparation of organotin compounds under Wurtz conditions, in which a mixture of the organic halide (RX) and tin halide is treated with metallic sodium (equation 4-19).24 This method can be used for both alkyl and aryl compounds, and involves the formation of RNa as an intermediate. However, the forma-... 

Preparation of Organotin Compounds in Lower Valence States... 

Since the various trialkylstannylmetals are available, their reactions with electrophiles provide a convenient methods for the preparation of organotin compounds. Substitutions of alkyl halides, tosylates, acetates, and sulfides with suitable stannyl-metals afford a variety of letraorganotin compounds (eq (136)) [131]. 

For the preparation of organotin compounds the procedure most widely applicable and that most often used in. the laboratory is to treat tin tetra-... 

The Stille reaction is a general Pd-catalyzed cross-coupling reaction [3, 13], that owes its popularity in part to the easy preparation of organotin compounds and then-tolerance toward most functional groups (Eq. 11.5). 

Boboli, E., Industrial methods for preparation of organotin compounds for production of thermal stabilizers for poly(vinyl chloride) and other chlorinated polymers," Przem. Chem. 377-6 (I967) CA 68j 87769. 

A new process has recently been described for the preparation of organotin compounds (117) by electrolysis of alkyl halide solutions in butyl acrylate (or other ester) with added bromine and stannous bromide. The anode was tin and the cathode nu esium. The authors noticed that the magnesium cathode disintegrated during electrolysis, and the process probably takes place through intermediate formation of an organomagnesium compound. 

Synthetic and mechanistic aspects of the reactions of the alkali-metal derivatives of organotin compounds, RaSnM ("organostannylan-ionoids ) have been reviewed (79, 80). They may be prepared by reactions of the types shown in the following equations. 

The preparation of trialkyltin compounds of lithium, RgSnLi, and their use for preparing the organotin compounds, RaSnR, has been discussed in a previous section. 

The use of organotin compounds for the preparation of organometallics and organometalloids appears to be quite versatile.9 For example, alkyltetrafluorophosphoranes have been obtained from tetraalkyltin compounds and phosphorus(Y) fluoride,10 phenylmercury(II) chloride from tetraphenyltin and mercury(II) chloride,11 and divinylbromoarsine from ( -C4H9)2-Sn(CH=CH2)2 and arsenic (III) bromide.12... 

That Grignard reagents are widely used for the preparation of various types of organotin compounds is further illustrated by l-trimethylstannyl-2-phenylethene, isolated120 in 63% yield, besides 1,4-diphenylbutadiene (28%) as a side-product. 

Testa and Dooley34 have also prepared several organotin compounds labelled with specific isotopes of tin. Tetrabutyltin-124 was prepared in 80% yield by reacting... 

Ebdon et al. [88] have discussed a programme to improve the quality of analytical results in the environmental monitoring of organotin compounds. They discuss the evolution of a sensitive, reliable and robust analytical method for the determination of tributyltin, with emphasis on the difficulties of determining it at the ng per litre levels at which it was usually encountered, more especially as other forms of tin frequently occurred together at similar levels. The preparation of a standard reference sample, for use in interlaboratory comparative determinations, under the aegis of the Bureau of Community Reference of the EU is described, and plans for subsequent distributions of blank, artificially spiked, and genuinely affected sediments are sketched. 

Physicians called attention to the effective antimicrobial action of organotin compounds in the middle of the last century. In 1958, Stalinon , a medical preparation consisting of diethyldiiodostannane and isolinolenic acid esters1072, was produced in France for the treatment of staphylococcus infections. Hexabutyldistannoxane in combination with formaldehyde1046 was used as a remedy against Staphylococcus aureus. 

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