Metalated Oligosilanylstibines

Abstract

The reaction of a cyclic disilylated bromostibine with magnesium yields a rare example of a magnesium stibide that can be silylated with trimethylchlorosilane. Reaction of the thus-obtained trisilylated stibine with potassium tert-butoxide gives a potassium stibide in a clean reaction. Attempts to obtain an antimony-containing oligosilanide did not lead to the expected compound but to another potassium stibide, which presumably forms from the initially formed silanide by a 1,2-silyl shift. The synthetic potential of the obtained stibides to serve as building blocks could be shown by the preparation of stibylated zircono- and hafnocenes.

Oligosilanylated Antimony Compounds

“…One may conclude that the reason for this is the steric bulk of the tris(trimethylsilyl)silyl group, but the effect is most likely electronic in nature because a trimethylsilylated stibacyclopentasilane ( 16 ) is also configurationally unstable. 25 All chemical shifts of 12 are within the expected ranges (Table 1 ). The NMR spectra of cyclotetrastibine 9 are completely as expected.…”

Synthesis and Structural Characterization of Magnesium‐Substituted Polystibides [(LMg)4Sb8]

“…[18] (13) . [19] Theeight Sb atoms in 1 can be divided into tricoordinated (Sb')a nd tetracoordinated (Sb'')a toms (Figure 2 (4) , which is in good agreement with those detected in {(Me 3 Si) 2 CH} 4 Sb 8 (2.784(4)-2.86184) ). [20] Note that the Sb'1ÀSb'2( 2.8580-(4) ) and Sb'3ÀSb'4(2.8582(4) ) distances of 1 are slightly longer than the Sb' À Sb'' bonds,which range from 2.7974(4) to 2.8209(4) ( molecule 1).…”

“…The Sb‐Mg‐Sb angles of 1 (87.07(3)–88.68(3)°) and 2 (84.76(8)°) are similar. The only structurally characterized magnesium stibide, [{Me 2 SiSi(SiMe 3 ) 2 } 2 SbMgBr(OEt 2 ) 2 ], shows a slightly shorter Mg−Sb bond length of 2.7806(13) Å . The eight Sb atoms in 1 can be divided into tricoordinated (Sb′) and tetracoordinated (Sb′′) atoms (Figure ).…”

Synthesis of Potassium Oligosilanides in Benzene

“…Oxacyclopentasilane 6 can be prepared from 4 via 4a . It can be regarded as a cyclic variation of 4 with a somewhat more exposed donor site and therefore was also subjected to metalation conditions with t BuOK in benzene.…”

“…Solvents were dried using a column solvent purification system . Tetrakis(trimethylsilyl)silane ( 1 ), triisopropylsilyltris(trimethylsilyl)silane ( 2 ), tert ‐butyldimethylsilyltris(trimethylsilyl)silane ( 3 ), 1,3‐bis[tris(trimethylsilyl)silyl]‐1,1,3,3‐tetramethyldisiloxane ( 4 ), 2,2,5,5‐tetramethyl‐3,3,4,4‐tetrakis(trimethylsilyl)‐1‐oxacyclopentasilane ( 6 ), tris(dimethylphenylsilyl)methylsilane ( 7 ), and 1,1,1,4,4,4‐hexakis(trimethylsilyl)tetramethyltetrasilane ( 10 ) were prepared following published procedures. Other chemicals were obtained from different suppliers and used without further purification.…”