Polyhedral Members of the Mg_2nP_2m Family Derived from Dimeric Magnesium Trialkylsilylphosphandiide

Abstract

The magnesiation of tri(tert-butyl)silylphosphane in THF yields tetrameric (tetrahydrofuran-O)magnesium tri(tert-butyl)silylphosphandiide 1. The central moiety is a slightly distorted Mg4P4 cube with tetracoordinate magnesium and phosphorus atoms. The reaction of dibutylmagnesium with H2PSitBu3 in toluene gives tetramagnesium tetrakis[mu-tri(tert-butyl)silylphosphanide] bis[mu 4-tri(tert-butyl)silylphosphandiide] 2. The central fragment is a Mg4P2 octahedron with the phosphorus atoms in a trans position. The Mg...Mg edges are bridged by the phosphanide substituents. Crystallographic data of 1: C68H148Mg4O5P4Si4, monoclinic, P2(1)/c, a = 13.454(1) A, b = 26.123(1) A, c = 24.539(2) A, beta = 96.53(1) degrees, Z = 4; crystallographic data of 2: C72H166Mg4P6Si6, monoclinic, P2(1)/n, a = 13.951(1) A, b = 14.269(1) A, c = 24.209(2) A, beta = 102.415(1) degrees, Z = 2.

Gold Phosphide Complexes

“…Although phosphide ligands, which are formed by deprotonation of non-tertiary phosphines, are closely related to the former, they have been employed to a lesser extent, mainly due to their lower stability. Thus, the chemistry of phosphido-bridged derivatives of the main group elements [1][2][3] or transition metals [4][5][6] has been a matter of interest for various research groups in the last few years. While there are many phosphido complexes with metals, mainly of groups 6 7-12 or 10, [13][14][15][16][17][18][19][20] the chemistry of gold derivatives has experienced less progress in this field of research in spite of the possible catalytic behaviour of di-and polynuclear phosphido-bridged compounds.…”

Synthese eines hexanuklearen Calcium–Phosphor-Käfigs über heteroleptische Calcium-amid-phosphanid-Vorstufen

“…Die Metallierung sterisch anspruchsvoller Trialkylsilylphosphane H 2 P±SiR 3 (R = i Pr [1], t Bu [2]) mit Dialkylmagnesium in THF fu È hrt zu tetrameren (Tetrahydrofuran)magnesium-trialkylsilylphosphandiiden mit einem zentralen Mg 4 P 4 -Heterocubanka È fig (R = i Pr [3], t Bu [4] [7] begu È nstigen, beobachtet man mit den kleineren Isopropylgruppen hexamere Moleku È le [SnPSi i Pr 3 ] 6 mit einem zentralen hexagonalen Sn 6 P 6 -Prisma [8].…”

“…At raised temperatures, 2 undergoes a homometallic metalation with the loss of two equivalents of HN(SiMe 3 ) 2 and dimerizes. The thus formed cage compound (THF) 2 Ca 6 [PSi t Bu 3 ] 4 [P(H)Si t Bu 3 ] 4 (3) with a central Ca 4 P 4 heterocubane moiety crystallizes upon cooling of the toluene solution. The molecular structures of 2 and 3 were determined.…”

“…Zwei gegenu È berliegende Fla È chen werden von (Tetrahydrofuran)calcium-bis[tri(tert-butyl)silylphosphanid]-Moleku È len u È berdacht. Damit gleicht dieses Moleku È l denjenigen der schwereren Erdalkalimetalle, wa È hrend Magnesium mit der Bildung homoleptischer Trialkylsilylphosphandiide eine Ausnahmestellung innerhalb dieser Gruppe einnimmt[3,4,11].…”

Alkaline Earth Organometallics

“…The equilibrium constants indicate that there is little difference between the R groups regarding [Mg(R)L 1 ] þ stability. It has been used to produce magnesium thiolates, 176-178 amides 179-184 (sometimes with heteroleptic alkyl/amide species), 180,185 carboxylato or carbamato complexes, 186 furfurylamides, 187 isothiocyanate and carbodiimide insertion products, 149 phosphides, 185,188-190 hydrazides, 191,192 phosphanediides, 193,194 arsandiides, 195 arsinoanilides, 196 aryloxides, [197][198][199] siloxides, 199 molecular hydrides, 200 4 . Alkylmagnesium amides, in particular, Mg(Bu)NPr i 2 , have been studied as new bases to address this issue.…”