Crystal Engineering with Oxo‐ and Cyanocarbon Anions: Synthesis and Structural Characterization of Triorganotin(IV) Pentacyanopropenides and Hexacyanoazapentadienides

The first triorganotin(IV) pentacyanopropenides, [ R 3 Sn(H 2 O) 2 ][C 3 (CN) 5 ] ( R = Me ( 2 ), n Bu ( 3 ), Ph ( 4 ) were prepared by treatment of Ag[C 3 (CN) 5 ] ( 1 ) with equimolar amounts of R 3 SnCl in reagent grade THF. In a similar manner, dark red [ R 3 Sn(H 2 O) 2 ][N{C(CN)C(CN) 2 } 2 ] ( 6 ) containing the hexacyanoazapentadienyl anion was prepared in 55 % yield. The molecular structure of [Ph 3 Sn(H 2 O) 2 ][C 3 (CN) 5 ] ( 4 ) was determined by X‐ray diffraction. The crystal structure consists of separated trigonal‐bipyramidal [Ph 3 Sn(H 2 O) 2 ] + cations and nearly planar [C 3 (CN) 5 ] – anions which are linked through O–H ··· N hydrogen bonds to give a three‐dimensional network.