Cation‐Triggered Stannate(II)/Stannylenoid/Stannylene Conversion

The reaction of dipotassio‐tetrasilan‐1,4‐diide ( 4 ) with anhydrous SnCl 2 at low temperature results in the formation of a five‐membered cyclic potassio chlorostannate(II) ([(18‐C‐6)K]( 1 )). By careful cation exchange reactions, it was transformed into the sodium chlorostannylenoid 2 (by using Na 2 [B 12 Cl 12 ]) or into the non‐stabilized cyclic bissilylstannylene 3 (through applying Li[Al(OC(CF 3 ) 3 ) 4 ]). The increasing Lewis basicity of the bissilylstannylene 3 was analyzed by combined methods of DFT calculations and NMR spectroscopy and substantiated by the synthesis of the corresponding iron carbonyl complexes 7 and 8 from the chlorostannate 1 and the stannylene 3 , respectively.