Synthesis tributylstannyl ethers

The generation of hydroxyketones by the brominolysiS of staimylenes has been used several times in total synthesis. Experiment G [see Eq. (IS)] describes a key step in the total synthesis of the antibiotic (+)-spectinomycin [12,13]. It is remarkable that the two oxygen atoms bound to the tin atom originate from hydroxyl groups, which are part of different fimctions, a hemiketal and a secondary alcohol. The oxidation is selective for one alccdiolic function out of three. The same product was obtained by A(-bromosuccinimide oxidation of the tributylstannyl ether. 

A stepwise Stille reaction enables the synthesis of unsymmetrical 3,3-diaryl-2-propen-l-ol derivatives. The first reaction occurs by replacement of the (Z)-substituted stannyl group of 3,3-bis(tributylstannyl)allyl methoxymethyl ether. ... 

Oxidative coupling. Methods for ketone synthesis by trapping electrophilic species generated by CAN oxidation with silyl enol ethers are quite useful. 2-Tributylstannyl-l,3-dithiane and l-trimethylsiloxy-l,3-butadiene are exemplary substrates. 

Trichlorosilyl enol ethers. The reaction of tributylstannyl enol ethers with SiCl results in trichlorosilyl analogs that are highly reactive as donors in aldol reactions without catalysts. Asymmetric synthesis in the presence of chiral phosphoramides is realized. 

Precaution Extremely flamm. sol ns. (> 20%) will ignite spontaneously in air ignites on contact with water or CO2 may cause potentially explosive polymerization of styrene NFPA Health 3, Flammability 4, Reactivity 2 Uses Solution polymerization initiator for polyolefin elastomers polymerization catalyst for food-contact polybutadiene for repeated use lithiation reagent Grignard-type reagent intermediate in prep, of lithium hydroxide org. synthesis reagent for metallation of org. compds. rocket fuel components to generate tetrahydrofurans from (tributylstannyl) methyl ethers... 

Addition of tributylstannyl-lithium to crotonaldehyde and protection of the resulting alcohol with chloromethyl methyl ether gives the stannane (192), which reacts with both alkyl and aryl aldehydes RCHO to form specifically the t/rr o-hydroxy-enol ethers (193). These latter compounds have been used to prepare tra/i5-4,5-disubstituted butyrolactones by hydrolysis and subsequent oxidation. Palladium-catalysed carbonylation of RX in the presence of organotin species constitutes a useful synthesis of unsymmetrical ketones, and in the example reported this year RX is an arenediazonium salt. The reaction, which is basically an aromatic acylation, proceeds in good to excellent yield. Another Pd-catalysed reaction of aromatics, this time aryl bromides, is their reaction with acetonyltributyltin (194), prepared from methoxytributyltin and isopropenyl acetate, to give the arylacetones (195). ... 

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