Triphenylstannyl-potassium

The reaction of trimethyl and triphenylstannyl potassium with mono- and di-substituted enones in acetonitrile as solvent led in nearly quantitative yields either to a mixture of diastereomers or to a pure diastereomer of /S-stannylketones (Scheme 41)109. There was experimental support for the existence of a SET mechanism, i.e. partial or total inhibition of the reaction by addition of a free radical scavenger (galvinoxyl) or a radical anion scavenger (p-dinitrobenzene). The possibility of a SET depends on the one-electron donor ability of the nucleophile and the electron acceptor ability of the ketone. These reactions are stereoselective. 

The crystal structure of triphenylstannylpotassium-[18]ane06, [Ph3Sn] [KCllSJaneOg)], where [ISJaneOs is the crown ether [18]crown-6 cyclo-(-OCH2CH2-)6 shows that the units in the crystal are crown ether-potassium ion complexes and pyramidal triphenylstannyl anions. The Mossbauer spectrum of this solid consists of a quadrupole-split doublet (5 2.17 mm s , ... 

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