Hydro stannation

Bu3SnH (AIBN) fail, but the corresponding bromide or iodide does undergo hydro-stannation in moderate yield. Consequently, the cyclization of 1 to 2 is probably not a radical reaction but involves benzylpalladation. The paper includes several other examples of this cyclic carbopalladation such as the conversion of 3 to 4. 

The hydrostannolysis of organic halides was discovered when an attempt at the hydro-stannation of allyl bromide resulted instead in hydrodebromination.37... 

Several reports on regioselective hydrostaimation have been published. In hydro-stannation of asymmetric diarylacetylene 90, stannation occurred regioselectively at the carbon close to the ort/io-substituted benzene to give 91 [26]. Hydrostanna-tion of the serine-derived ynoate 92 at —10 °C afforded the a-stannyl ester 93 with high regioselectivity (16 1), and the reaction was applied to the total synthesis of asperazine [27]. 

Concentrated nitric acid produces the hydrated tin(IV) oxide sometimes called metastannic acid. Tin evolves hydro n with hot alkali solutions to form alkali stannates. 

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