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Abstract: The SRN1 reactions of trimethylstannyl and triphenylstannyl anions, and other tin nucleophiles with haloarenes are quite versatile. Thus, the SRN1 mechanism can afford triorganylstannyl aromatic compounds which otherwise would be synthesized by routes employing harsher reaction conditions. The sequence SRN1-Pd-catalysis is a powerful synthetic tool, and the scope of the reaction is unlimited owing to the nature of the sequence, i.e. ArX → ArSnR3 → ArAr, which can be iteratively repeated when appropriate substituted substrates are chosen. From stannanes obtained by the SRN1 reaction, it is possible to obtain by electrophilic reactions aromatic ketones, or through transmetalation reactions to produce boronic acids that can be used in Suzuki reactions. Using the novel dianion Me2Sn−2, it is possible to synthesize Me2SnAr2, which by Cu catalysis reaction affords Ar–Ar through homocoupling reactions. By a new methodology, organotin compounds with a Sn- heteroatom bond can be obtained and by Stille reactions aryl phosphines, arsines, stibines and selenides can be synthetized, all in one-pot reaction. The triarylarsines can be used as ligands in cross-coupling reactions. From vinyl chlorides, it is possible to obtain vinylic stannanes, which by cross-coupling reactions afford aryl substituted alkenes. [Copyright &y& Elsevier]

Abstract: A selective two-step synthesis of either mono- or distannylated pyridines from commercially available pyridinols, involving its conversion to the corresponding diethyl pyridyl phosphates (pyDEP) followed by the reaction with Me3SnNa in liquid ammonia, is described. The results obtained clearly indicate that the reactions proceed through an unimolecular radical nucleophilic substitution mechanism (SRN1) with intermediacy of a monosubstitution product. [ABSTRACT FROM AUTHOR]

Abstract: A series of arylstannanes have been synthesized, through an SRN1 mechanism, in good to excellent yields (74%–99%) by the photostimulated reaction of trimethyl stannyl ion with substrates supporting different nucleofugal groups. The arylstannanes thus obtained were suitable intermediates for Stille cross-coupling reactions leading to asymmetric bi- and triaryl compounds in acceptable global yields. An attractive feature of this route is that simple commercially available benzenediols, chloro- and methoxy phenols might be useful starting substrates, leading the latter to higher global yields of products in fewer steps. The strategies proposed open a broad synthetic tool. [Copyright &y& Elsevier]