Cationic Brønsted Acids for the Preparation of SnIV Salts: Synthesis and Characterisation of [Ph3Sn(OEt2)][H2N{B(C6F5)3}2],[Sn(NMe2)3(HNMe2)2][B(C6F5)4] and [Me3Sn(HNMe2)2][B(C6F5)4]

Yann Sarazin (1) , Simon J. Coles (2) , David L. Hughes (1) , Michael B. Hursthouse (2) , Manfred Bochmann (1)

1 UEA - University of East Anglia [Norwich]
2 NCS - National Crystallography Service

Ph3SnN(SiMe3)2 (1) was prepared in good yields by reaction of [{NaN(SiMe3)2}2·THF] (2) with Ph3SnF. Treatment of 1 with [H(OEt2)2][H2N{B(C6F5)3}2] (4) in dichloromethane afforded the stannylium cation [Ph3Sn(OEt2)][H2N{B(C6F5)3}2] (5), which was characterised by 1H, 13C{1H}, 11B, 19F and 119Sn NMR spectroscopy. The reaction of Sn(NMe2)4 with [Ph2MeNH][B(C6F5)4] (3) gave the amidotin(IV) compound [Sn(NMe2)3(HNMe2)2][B(C6F5)4] (6) which proved very stable towards ligand substitution and resisted treatment with Et2O, THF, TMEDA and pyrazine. Two new Brønsted acid salts [H(NMe2H)2][B(C6F5)4] (7) and [(C4H4N2)H·OEt2][H2N{B(C6F5)3}2] (8) were synthesised. The reaction of 7 with Sn(NMe2)4 in Et2O allowed the preparation of 6 in a much improved yield (83%). The treatment of 7 with Me3SnN(SiMe3)2 in Et2O yielded [Me3Sn(HNMe2)2][B(C6F5)4] (9) nearly quantitatively. Compounds 1, 2, 6, 8 and 9 were characterised by single-crystal X-ray diffraction analyses; 6 is the first example of a structurally characterised amidotin(IV) cation.

Domaines: Chimie

Yann Sarazin, Simon J. Coles, David L. Hughes, Michael B. Hursthouse, Manfred Bochmann. Cationic Brønsted Acids for the Preparation of SnIV Salts: Synthesis and Characterisation of [Ph3Sn(OEt2)][H2N{B(C6F5)3}2],[Sn(NMe2)3(HNMe2)2][B(C6F5)4] and [Me3Sn(HNMe2)2][B(C6F5)4]. European Journal of Inorganic Chemistry, 2006, 2006 (16), pp.3211 - 3220. ⟨10.1002/ejic.200600397⟩. ⟨hal-01445044⟩