Alkalisilanolate und -siloxanolate als Precursor für Si–O-Ringe / Alkali Silanolates and Siloxanolates as Precursors for Si–O Rings

Abstract

The disilanol (CMe3)2Si(OH)2 (1) serves as a starting material in the reaction with C4H9Li and sodium for the construction of the alkali derivatives 2,3,4, and the siloxanes 5,6,7,8. The six-membered cyclosiloxane 10 and the spirocyclic compound 11 are easily prepared in the reaction of [(Me3C)2Si(OH)]2O (8) with 2C4H9Li and SiF4 or SnBr4. The crystal structures of (Me3C)2Si(OLi)2 (3), (Me3C)2Si(ONa)OH (4), and (Me3C)2Si(ONa)OSiF(Me3C)2 (9) have been determined and are discussed.

f-Element Disiloxanediolates: Novel Si−O-based Inorganic Heterocycles

“…IR spectra were recorded on a Perkin ± Elmer FTIR Spectrometer System 2000. NMR spectra were recorded on a Bruker DPX FT-NMR spectrometer ( 1 H 400 MHz, 13 C 101 MHz, 29 Si 79.5 MHz). Chemical shifts are reported in ppm and referenced to residual solvent resonances ( 1 H, 13 C) or an external standard ( 29 Si, TMS d 0).…”

“…NMR spectra were recorded on a Bruker DPX FT-NMR spectrometer ( 1 H 400 MHz, 13 C 101 MHz, 29 Si 79.5 MHz). Chemical shifts are reported in ppm and referenced to residual solvent resonances ( 1 H, 13 C) or an external standard ( 29 Si, TMS d 0). Elemental analyses were performed at the Chemistry Department of the Otto-von-Guericke-Universität using a Leco CHNS 932 apparatus.…”

“…M.p. 105 8C (dec); IR (Nujol): n Ä 3135w, 3068m, 3047m, 3017(sh)m, 3000m, 2978m, 2881m, 1961w, 1892w, 1831, 1774w, 1618w, 1591m, 1568w, 1486w, 1459w, 1428s, 1376w, 1306w, 1263m, 1186m, 1119vs, 1039vs, 1018vs, 995vs, 954vs, 743s, 714vs, 701vs, 684s, 620m, 534vs, 492vs cm À1 ; 1 H NMR ([D 8 ]THF, 400 MHz): d 7.85 ± 7.00 (m, Ph), other resonances could not be assigned due to strong broadening as an effect of the paramagnetic Nd 3 ion; 13 [{{Ph 2 Si(OSiPh 2 O) 2 }{Li(MeCN)} 2 } 2 ] (5): Ph 2 Si(OH) 2 (0.22 g, 1.0 mmol) was added in small portions over a period of 30 min to a stirred solution of 3 (0.7 g, 0.5 mmol) in THF (40 mL). After about one-half of silanediol had been added, a gelatinous white precipitate started to form.…”

Structurally different divalent metallasiloxanes [Mg{O(Ph2SiO)2}2]-μ-(LiPy)-μ-{(LiPy)3(OH)(Cl)}], [Cr{O(Ph2SiO)2}-μ-(LiPy2)2], and [{O(Ph2SiO)2}Co{O(Ph2SiO)3)}-μ-(LiPy2)2] from Ph2Si(OH)2/2BuLi and the metal dichlorides

“…(THF), [14]. In addition, the structures of the monolithium and monosodium derivatives of related silane diol t-Bu2Si(OH)2, [t-Bu2Si(OH) (OLi).THF]4 and [t-Bu2Si(OH) (ONa).THF]6 have been reported [15,16]. Despite the ill-defined nature of the product or products from Ph2Si(OH)2/BuLi (l:2) we have used this in situ generated material in reactions with the metal dichlorides MgCb, CrCb_ and COC12 and isolated the compounds 1, 2, and 3 (molecular cores shown below).…”

Encapsulation of molecular Na2SiF6 by two metallacrown complexes

“…11 Structural data on molecular complexes in which sodium atoms are coordinated to SiF groups are rare. The Na(m-F)Si arrangement has been observed for [ t Bu 3 Si(ONa)OSi t Bu 2 F] 3 (Na-F 2.30-2.37 Å), 12 for [ t Bu 3 SiFNa(THF) 2 PC 6 H 2 Me 3 ] 2 (Na-F 2.383(2) Å), 13 and for a dimeric sodium phosphanide (Na-F 2.262(5) Å). 14 The Na(m-F) 3 Si(m-F) 3 Na molecule is well shielded by the sterically demanding cymene p-ligands (Fig.…”