Synthesis and Structure of Semi(tetrahydrofuran-O)bispotassium Bis(2,3,4,5-tetraethylstibolide)

Abstract

The reaction of bis(cyclopentadienyl) zircona-2,3,4,5-tetraethylcyclopentadiene (1) with antimony trichloride yields 1-chloro-2,3,4,5-tetraethyl-1-stibole (2). The reduction with potassium gives semi(tetrahydrofuran-O)bispotassium bis (2,3,4,5-tetraethylstibolide) (3). The potassium stibolide columns are linked via K-Sb contacts of 3.618 Å, thus forming a wavelike layer structure. The molecular structure shows three crystallographically different metal cations. One potassium atom is located between two stibolide anions, whereas the other ones show additional K-O and K-Sb contacts of 2. 681 and 3.618 Å, respectively.

Metalated Oligosilanylstibines

“…One DME molecule is coordinating to each potassium atom, and for one of the two molecules, the DME is disordered in the ethylene bridge. The potassium–antimony distance is 3.5320(9) Å, in good accordance to the few comparable structures known in the literature (3.566, 33 3.686, 24 and 3.618 34 Å), although none of these displays the structural element of a four-membered ring. This Sb–K–Sb–K ring is planar, whereas the stibacyclopentasilane rings both engage in envelope conformations with one of the SiMe 2 groups on the flap.…”

Interpnictogen Compounds with Polarised Phosphorus–Element Bonds

“…By analogy, coupling of 6a with chloroarsane 5b 5 and chlorostibane 5c 5 gave the expected products 2 , 3 with As–P and Sb–P bonds, and treatment of 5a with lithium arsolide 6b 6 produced 4 which is set apart from 2 by formal exchange of the two pnictogen atoms (Scheme ). In contrast, reaction of chlorophosphane 5a with the potassium stibolide [K(SbC 4 Et 4 )] ( 6c ) 7 was found to be messy, and we were unable to obtain an isolable product. The interpnictogen compounds 2 – 4 were isolated in moderate to good yields of 50–72 % and characterised by analytical and spectroscopic data and single‐crystal diffraction studies.…”

Untitled

“…101 K[SbC 4 Et 4 ] has been prepared from the reaction of 1-chloro-2,3,4,5-tetraethyl-1-stibole and potassium. 102 The solid-state structure of the THF adduct shows both h 1 -and h 5 -coordination to K + .…”