A versatile salt-metathesis route to heteroatomic clusters derived from phosphorus and arsenic Zintl anions

Abstract

Salt metathesis reactions between ethylenediamine (en) solutions of the K₃E₇ (E = P, As) Zintl phases and post-transition metal halides (InCl₃, TlCl, SnI₂ and PbI₂) have yielded a family of novel heteroatomic cluster anions, [In(E₇)₂]³⁻, [TlE₇]²⁻ and [E′E₁₅]³⁻ (E′ = Sn, Pb; E = P, As). Several of these new species have been characterized by single-crystal X-ray diffraction as salts of sequestered potassium cations in [K(2,2,2-crypt)]₃[In(P₇)₂]·3.5py (1), [K(2,2,2-crypt)]₂[TlP₇]·py (3), [K(18-crown-6)]₂[TlAs₇] (4b), [K(2,2,2-crypt)]₃[E′P₁₅]·en (E′ = Sn (5), Pb (6)) and [K(2,2,2-crypt)]₃[SnAs₁₅]·2en (7). The presence of all of the cluster anions in solution was confirmed by electrospray mass-spectrometry and by ¹H and ³¹P{¹H} NMR spectroscopy when pertinent.