effect of Diverse Ligands on the Course of a Molecules-to-Solids Process and Properties of Its Intermediates

Abstract

Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. .) The different clusters form when different supporting phosphine ligands are employed. We report the syntheses, structures, and properties of these intermediates and the comparisons and contrasts between these molecular intermediates and the extended solid products. We note that when larger ligands are used smaller clusters are formed. We also note what features of the molecular structures lead to ferromagnetic versus antiferromagnetic coupling of the distinct Fe centers. We have determined the structures of the following materials crystallographically: 2 (C 36 H 84 Fe 4 Te 4 P 4 ; tetragonal, P421c; a = 14.0469(7) Å, c = 13.5418(9) Å; Z = 2); 3 (C 18 H 54 Fe 6 Te 8 P 6 ; trigonal, R3; a = 11.859(2) Å, c = 26.994(5) Å; Z = 3); dmpe·2Te (C 6 H 16 Te 2 P 2 ; monoclinic, P2 1 /c; a = 6.0890(4) Å, b = 10.7934(7) Å, c = 9.8200(5) Å, β = 104.63 (7)

Molecular structure of n-tributylphosphine telluride

“…The spatial arrangement of the P atom is distorted tetrahedral. The PϪTe bond length of n -Bu 3 PTe [2.368 (1) Å ] compares well with those of t -Bu 3 PTe [2.368 (4) Å ] (Kuhn et al, 1987), i -Pr 3 PTe [2.366 (1) Å ] (Kuhn et al, 1990), and Me 2 P(Te)CH 2 CH 2 P(Te) Me 2 [2.357 (2) Å ] (Steigerwald et al, 1994) and points to 1.113 R 1 ( F ) (I > 2 σ (I)) 0.0307 wR 2 ( F 2 ) (all data) 0.0808 ( Δ / σ ) max < 0.001 Largest difference peak/hole, e Å -3 0.898/-1.479 Table 1 Crystal data and structure refinement of n -Bu 3 PTe.…”

“…The distortion is reflected by the mean TeϪPϪC and CϪPϪC angles [112.9(1) ° and 105.9(1) ° ] that are in good agreement with those of Me 2 P(Te)CH 2 CH 2 P(Te)Me 2 [113.5(3) ° and 105.2(4) ° ] (Steigerwald et al, 1994). In contrast, the mean TeϪPϪC and CϪPϪC angles of t -Bu 3 PTe [108.7(4) ° and 110.2(5) ° ] (Kuhn et al, 1987) and i -Pr 3 PTe [110.9(1) ° and 110.7 (1) ° ] (Kuhn et al, 1990) are much closer to the ideal tetrahedral angle of 109.3 ° .…”

“…In organometallic synthesis, n -Bu 3 PTe has been utilized as a mild transfer reagent for atomic tellurium (Sasamori et al, 2005;Tajima et al, 2006). A literature search brought forward that only three trialkylphosphine tellurides have been investigated by X-ray crystallography, namely, t -Bu 3 PTe (Kuhn et al, 1987), i -Pr 3 PTe (Kuhn et al, 1990), and Me 2 P(Te)CH 2 CH 2 P(Te)Me 2 (Steigerwald et al, 1994). Here, we report the molecular structure of n -Bu 3 PTe, which is shown in Figure 1 .…”

Successful oxidation of Ph2P(CH2)nPPh2 (n = 2, 4, 6) by tellurium leading to Ph2P(Te)(CH2)nP(Te)Ph2

“…So far, the only structurally characterized ditelluro R 2 P(Te)(CH 2 ) n P(Te)R 2 compound is Me 2 P(Te)(CH 2 ) 2 -P(Te)Me 2 , which was not prepared by direct oxidation by elemental tellurium, but by a tellurium transfer reaction between Et 3 PTe and Me 2 P(CH 2 ) 2 PMe 2 . 9 In the case of structurally analogous R 2 PNHPR 2 compounds (R ¼ alkyl, aryl), a monotelluro P-H tautomer iPr 2 P(Te)NP(H) iPr 2 was successfully prepared by reaction of iPr 2 PNHPiPr 2 with elemental tellurium. 10 The synthesis of ditelluro salts TME-DA$Na[R 2 P(Te)NP(Te)R 2 ] was again successful when using the deprotonated [R 2 PNPR 2 ] À species (R ¼ iPr, 11 tBu, 12 Ph 13 ) as starting materials.…”

Reaction of CH2(Ph2PSe)2 (dppmSe2) with [Ru3(CO)12]. Fluxional behaviour of [Ru3(μ3-Se)2(CO)7(μ-dppm)] and crystal structures of [Ru4(μ4-Se)2(μ-CO)(CO)8(μ-dppm)]·MeOH and [Ru6(μ3-Se)4(CO)12(μ-dppm)2]·CH2Cl2

“…The control over the stoichiometric ratio, combined with the kinetic control, which derives from low activation energies of these processes, could allow the synthesis of otherwise inaccessible solid phases or microinhomogeneous materials such as nanocomposites. 2 Despite the synthetic potential of the phosphine selenides, their reactions with metal carbonyls have been explored only to a limited extent prior to the last three years and, in general, most of the previously described chalcogenido-carbonyl clusters containing Group 15 donor ligands had been obtained by substitution reactions. 3 As regards chelating diphosphine selenides, we have recently found that the reactions of [Fe 3 (CO) 12 ] with three diphosphine diselenides dppmSe 2 , dppeSe 2 and dppfcSe 2 produce the substituted 50-electron, nido clusters Fe, dppfc) as the main products.…”