From vinyltin reagents

Palladium-catalyzed allylic alkylation by transmetallation with Grignard reagents is less frequently encountered than with aryl- and vinyltin reagents [85]. However, a few examples are known from the literature and reported herein. In some cases, if the reactivity of such allylic-ethers or amines have been reported, the regioselectivity was not studied because of the symmetric nature of the substrates. 

In the presence of a soft nucleophile, the unstable intermediate vinyllead triacetate (87) behaves as a C-vinylating reagent, whatever the mode of formation of the vinyllead intermediate (metal-metal exchange from divinylmercury or from vinyltin compounds). 

Reaction of 140 with vinyltin reagent yields the cyclized product 141. The conversion can be understood by cis carbopalladation, transmetallation with the Sn reagent, and reductive elimination [45,46]. This reaction is overall cis addition to the triple bond. The intramolecular version of furan synthesis was plied to the preparation of the key intermediate of halenaquinone and halenaquinol syntheses from 142 [47]. 

Xenon difluoride is a better fluorinaling reagent for vinyltin compounds than cesium fluoroxysulfate (compare entry 1 in Tables 1 and 2). Besides this, cesium fluoroxysulfate (which can be prepared from elemental fluorine and cesium sulfate) is known to be shock sensitive and to undergo detonation upon hcaling. However, cesium fluoroxysulfate is the alternative choiee in the ease of some vinyltin compounds, such as 2- and 3-(trimethylstannyl)indolcs (Table 2, entries 5 7), whose reactions with xenon difluoride are not effective. 

Vinyltin compounds can be generated from the corresponding vinyl-Grignard reagents or vinyllithium compoimds with a... 

---