Organosubstituierte 1,1′‐Spirobisilole und 1,1′‐Spirobigermole durch vierfache Organoborierung von Tetra‐1‐alkinylsilanen und ‐germanen

Abstract

5f, 5g, 6f, 8f, 9g, log, l l g ) of which only 9 g (R = Ph) corresponds to the spirosilanes and -germanes. This is the result of effective competition between intramolecular and intermolecular organoboration in the case of the tetra-1-alkynyltin compounds. The protodeborylation of l a , b and 2d, e with MeCOzH leads to 12a, b and 13d, e, respectively. 12a isomerises by UV irradiation to ally1 isomers 12a'. From 12a with 2 equiv. of maleic anhydride the 1:2 addition compound 14a is obtained, the autaddition of 12a, d leads to 15a, d. Spiro compound 12a reacts with (OC)5Fe or CpCo(C,H,), to give the cyclodiastereomeric q4-complexes [(OC)3Fe]z-12a (16al-a,; X-ray structure analysis of meso16a1), (OC)3Fe-12a (17a) and (CpCo),-12a (18al-a4). -All products were characterized by multinuclear NMR, including measurements of the coupling constants 1J(13C13C), 2J(zgSizgSi), nJ(29Si13C) and nJ("gSn'3C).

Hybrid Silicon Nanostructures with Conductive Ligands and Their Microscopic Conductivity

“…3b, which are consistent with carbons in six different environments within the molecule. 12 These spectra are in agreement with the previous results measured on the phenylacetylene-capped SiNPs. 1 The ALC resonances that are observed are around 2.2 T for both the compound and the nanoparticle samples (see Fig.…”

Metallacyclopentadienes and related heterocycles via 1,1‐organoboration of alkyn‐1‐ylmetal compounds

“…which has been partly analyzed [51]. Although stannoles are present in this mixture, they could not be isolated in pure state.…”

“…Both dialkyn-1-yl(diorgano)germanium, Me 2 Ge(C C-R 1 ) 2 , and tetraalkyn-1-ylgermanium compounds, Ge(C C R 1 ) 4 , have been studied in their reactivity toward triethylborane [51]. This has led to the germoles 33 [7,55] and spirogermanium compounds (1,1 -spirobigermoles) 34 [51] (Scheme 17). In the case of Me 2 Ge(C C R 1 ) 2 the germole 33 was also obtained for R 1 = OMe [56].…”

Combination of 1,2‐Hydroboration and 1,1‐Organoboration: A Convenient Route to 5‐Silaspiro[4,4]nona‐1,6‐diene Derivatives

“…In addition to numerous saturated spirosilanes and a few examples of 5-silaspiro[4,4]nona-2,7-dienes, [3,4] previous work has shown that ethylboration of tetraalkyn-1-ylsilanes, Si(CϵC-R) 4 , provides a straightforward route to 1,1-spirobisiloles A. [5][6][7] Recently, we characterized the first spirosilanes containing two four-membered rings B by using 1,2-hydroboration and 1,1-organoboration. [8] The combination of these stereo-and regioselective reactions is attractive in synthesis, [8][9][10] and in the present work further examples are given that are aimed at the synthesis and first structural characterization of the hitherto unknown 5-silaspiro[4,4]nona-1,6-diene derivatives.…”