Synthesis and structure of crystalline [K{Sn(CH₂Bu^t)₃}(η-C₆H₅Me)₃] and the first NMR spectral observation of¹¹⁹Sn–³⁹K coupling

Abstract

Treatment of [Sn2(CH2But)6] with K in tetrahydrofuran (thf) at 25 °C affords crystalline [K{Sn(CH2But)3}(thf)2]1, which with toluene gives [K{Sn(CH2But)3}(η6-C6H5Me)3]2, the X-ray structure of 2 at 295 K revealing that potassium is in a distorted tetrahedral environment (taking each of the η6-toluene molecules as occupying a single site), with l(K–Sn) 3.548(3)Å and l(K–C) ranging from 3.21 to 3.72 Å; a solid state 1l9Sn cross-polarisation magic angle spinning (CP-MAS) NMR spectral study of 2 provides the first observation of direct 119Sn–39K coupling.