Silicon‐ and Tin‐Containing Open‐Chain and Eight‐Membered‐Ring Compounds as Bicentric Lewis Acids toward Anions

Herein, we report the syntheses of silicon‐ and tin‐containing open‐chain and eight‐membered‐ring compounds Me 2 Si(CH 2 SnMe 2 X) 2 ( 2 , X=Me; 3 , X=Cl; 4 , X=F), CH 2 (SnMe 2 CH 2 I) 2 ( 7 ), CH 2 (SnMe 2 CH 2 Cl) 2 ( 8 ), cyclo ‐Me 2 Sn(CH 2 SnMe 2 CH 2 ) 2 SiMe 2 ( 6 ), cyclo ‐(Me 2 SnCH 2 ) 4 ( 9 ), cyclo ‐Me (2− n ) X n Sn(CH 2 SiMe 2 CH 2 ) 2 SnX n Me (2− n ) ( 5 , n =0; 10 , n = 1, X= Cl; 11 , n =1, X= F; 12 , n =2, X= Cl), and the chloride and fluoride complexes NEt 4 [ cyclo ‐ Me(Cl)Sn(CH 2 SiMe 2 CH 2 ) 2 Sn(Cl)Me⋅F] ( 13 ), PPh 4 [ cyclo ‐Me(Cl)Sn(CH 2 SiMe 2 CH 2 ) 2 Sn(Cl)Me⋅Cl] ( 14 ), NEt 4 [ cyclo ‐Me(F)Sn(CH 2 SiMe 2 CH 2 ) 2 Sn(F)Me⋅F] ( 15 ), [NEt 4 ] 2 [ cyclo ‐Cl 2 Sn(CH 2 SiMe 2 CH 2 ) 2 SnCl 2 ⋅2 Cl] ( 16 ), M[ M e 2 Si(CH 2 Sn(Cl)Me 2 ) 2 ⋅Cl] ( 17 a , M=PPh 4 ; 17 b , M=NEt 4 ), NEt 4 [ M e 2 Si(CH 2 Sn(Cl)Me 2 ) 2 ⋅F] ( 18 ), NEt 4 [ M e 2 Si(CH 2 Sn(F)Me 2 ) 2 ⋅F] ( 19 ), and PPh 4 [ M e 2 Si(CH 2 Sn(Cl)Me 2 ) 2 ⋅Br] ( 20 ). The compounds were characterised by electrospray mass‐spectrometric, IR and 1 H, 13 C, 19 F, 29 Si, and 119 Sn NMR spectroscopic analysis, and, except for 15 and 18 , single‐crystal X‐ray diffraction studies.