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21.
Hitchcock PB Lappert MF Liu DS Sablong R 《Chemical communications (Cambridge, England)》2002,(17):1920-1921
The compounds [K((mu-N(SiMe3)C(Ph))2CH)(thf)2]infinity 1, [K(mu-N(SiMe3)C(Ph)C(H)C(Ph)NH)L]2 [L = (thf)2 2, tmen 3], [K(mu-NSi(Me)2C(Ph)C(H)C(Ph)N)(thf)3]2 4 and [K(N(H)C(Ph))2CH](thf)0.5 5 have been prepared from K[(N(SiMe3)C(Ph))2CH] and the X-ray structures of 1-4 are reported. 相似文献
22.
23.
al-Ktaifani MM Bauer W Bergsträsser U Breit B Francis MD Heinemann FW Hitchcock PB Mack A Nixon JF Pritzkow H Regitz M Zeller M Zenneck U 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(11):2622-2633
Several independent synthetic routes are described leading to the formation of a novel unsaturated tetracyclic phosphorus carbon cage compound tBu4C4P6 (1), which undergoes a light-induced valence isomerization to produce the first hexaphosphapentaprismane cage tBu4C4P6 (2). A second unsaturated isomer tBu4C4P6 (9) of 1 and the bis-[W(CO)5] complex 13 of 1 are stable towards similar isomerization reactions. Another starting material for the synthesis of the hexaphosphapentaprismane cage tBu4C4P6 (2) is the trimeric mercury complex [(tBu4C4P6)Hg]3 (11), which undergoes elimination of mercury to afford the title compound 2. Single-crystal X-ray structural determinations have been carried out on compounds 1, 2, 9, 11, and 13. 相似文献
24.
Jos Ruiz M. Teresa Martínez Consuelo Vicente Venancio Rodríguez Gregorio Lpez Jos Prez Penny A. Chaloner Peter B. Hitchcock 《无机化学与普通化学杂志》2005,631(11):2227-2231
Mononuclear palladium‐hydroxo complexes of the type [Pd(N–N)(C6F5)(OH)][(N–N) = 2,2′‐bipyridine (bipy), 4,4′‐dimethyl‐2,2′‐bipyridine (Me2bipy), 1,10‐phenantroline (phen) or N,N,N′,N′‐tetramethylethylenediamine (tmeda) react with phenols ArOH in tetrahydrofuran giving the corresponding aryloxo complexes [Pd(N–N)(C6F5)(OAr)]. Elemental analyses and spectroscopic (IR, 1H and 19F) methods have been used to characterize the new complexes. The X‐ray crystal structure of [Pd(tmeda)(C6F5)(OC6H4NO2‐p)] has been determined. In the crystal packing the planes defined by two C6H4 rings show a parallel orientation. There are also intermolecular C–H···F and C‐H···O hydrogen bonds. 相似文献
25.
Hitchcock PB Hu J Lappert MF Severn JR 《Dalton transactions (Cambridge, England : 2003)》2004,(24):4193-4201
Treatment of [Li(L1)]2 (1) or K(L2) (2) with SnX2 in Et2O yielded the heteroleptic beta-diketiminatotin(II) halides Sn(L1)Cl (3a), Sn(L1)Br (3b) or Sn(L2)Cl (4), even when an excess of the alkali metal beta-diketiminate was used [L1={N(R)C(Ph)}2CH, L2={N(R)C(Ph)CHC(But)N(R)}, R = SiMe3]. From and half an equivalent each of SnCl2.2H2O and SnCl2, or one equivalent of SnCl2.2H2O, the product was Sn(L3)Cl (5) or Sn(L4)Cl (6), in which one or both of the N-R bonds of L1 had been hydrolytically cleaved; the compound Sn(L5)Cl (7) was similarly obtained from and an equivalent portion of SnCl2.2H2O [L3={N(R)C(Ph)CHC(But)N(H)}, L4={N(H)C(Ph)CHC(But)N(H)} and L5={N(H)C(Ph)}2CH]. The halide exchange between 3a and 3b, studied by two-dimensional (119)Sn{1H}-NMR spectroscopy, is attributed to implicate a (mu-Cl)(mu-Br)-dimeric intermediate or transition state. The 13C{1H}-NMR spectra of or showed two distinct resonances for each group, which coalesced on heating, corresponding to DeltaG(338 K)= 69.4 (3a) or 72.8 (3b) kJ mol(-1). The chloride ligand of was readily displaced by treatment with NaNR2, CF3SO3H or CH2(COPh)2, yielding Sn(L1)X [X = NR2 (8), O3SCF3 (9) or {OC(Ph)}2CH (10)]. Oxidative addition of sulfur or selenium to gave the tin(IV) terminal chalcogenides Sn(E)(L1)(NR2)[E = S (11) or Se (12)]. The X-ray structures of the cocrystal of 3a/3b and of the crystalline compounds 5, 6, 8, 11 and are presented, as well as multinuclear NMR spectra of each of the new compounds. 相似文献
26.
Farwell JD Hitchcock PB Lappert MF Protchenko AV 《Chemical communications (Cambridge, England)》2005,(17):2271-2273
The crystalline compounds [Mg(Br)(L)(thf)].0.5Et2O [L = {N(R)C(C6H3Me2-2,6)}2SiR, R = SiMe3] (1), [Mg(L){N=C=C(C(Me)=CH)2CH2}(D)2] [D = NCC6H3Me2-2,6 (2), thf (3)] and [{Mg(L)}2{mu-OSO(CF3)O-[mu}2] (4) were prepared from (a) Si(Br)(R){C(C6H3Me2-2,6)=NR}2 and Mg for (1), (b) [Mg(SiR3)2(thf)2] and 2,6-Me2C6H3CN (5 mol for (2), 3 mol for (3)), and (c) (2) + Me3SiOS(O)2CF3 for (4); a coproduct from (c) is believed to have been the trimethylsilyl ketenimide Me3SiN=C=C{C(Me)=CH}2CH2 (5). 相似文献
27.
Colin Eaborn Peter B. Hitchcock Paul D. Lickiss 《Journal of organometallic chemistry》1981,221(1):13-17
The structure of the crowded molecule (Me3Si)3C(SiMe2Ph) has been determined by single crystal X-ray diffraction. The steric strain manifest itself mainly in lengthening of the Me3SiC and Me2PhSiC bonds (average length 1.920(6) ) and closing up of the CSiC angles within the Me3Si and Me2PhSi groups (average 105.2(10)°), with correspondingly large C(1)SiC angles (113.5(13)°; C(1) is the central carbon atom). 相似文献
28.
Gehrhus B Hitchcock PB Parruci M 《Dalton transactions (Cambridge, England : 2003)》2005,(16):2720-2725
The thermally stable silylene Si[(NCH2But)2C6H4-1,2] 1 undergoes oxidative addition reactions with the lithium amides LiNRR'(R = SiMe3, R' = But; R = SiMe3, R' = C6H3Me2-2,6; R = R' = Me or R = R' = Pri) to afford the new lithium amides Li(THF)2[N(R)Si(SiMe3){(NCH2But)2C6H4-1,2}][R = But2 or R = C6H3Me2-2,6 (3a)] or the new tris(amino)functionalised silyllithiums Li(THF)x[Si{(NCH2But)2C6H4-1,2}NRR'][R = SiMe3, R' = C6H3Me2-2,6, x = 2 (3); R = R'= Me, x = 3 (4) or R = R' = Pri, x = 3 (5)]. Compounds 4 and 5 are stable at ambient temperature but compound 3 is thermally labile and converts into 3a upon heating. The pathway for the formation of 2 and 3 is discussed and the X-ray structures of 2-5 are presented. 相似文献
29.
Crystalline [Li{N(SiMe2OMe)C(tBu)C(H)(SiMe3)}]2 (5), [Li{N(SiMe2OMe)C(Ph)C(H)(SiMe3)}]2 (6), [C(C6H3Me2-2,5)C(H)(SiMe3)}(TMEDA)](7), [Li{N(SiMe(OMe)2)C(tBu)C(H)(SiMe3)}(THF)]2 (8), Li{N(SiMe(OMe)2)C(Ph)C(H)(SiMe3)}(TMEDA) (9) and [Li{N(SiMe2OMe)C(tBu)C(H)(SiMe2OMe)}]2 (10) were readily obtained at ambient temperature from (i) [Li{CH(SiMe3)(SiMe2OMe)}]8 (1) and an equivalent portion of RCN (R=tBu (5), Ph (6) or 2,5-Me2C6H3 (7)); (ii) [Li{CH(SiMe3)(SiMe(OMe)2)}]∞ (2) and an equivalent portion of tBuCN (8) or PhCN (9); and (iii) [Li{CH(SiMe2OMe)2}]∞ (3) and one equivalent of tBuCN (10). Reactions (i) and (ii) were regiospecific with SiMe3−n(OMe)n>SiMe3 in 1,3-migration from C (in 1 or 2)→N. The 1-azaallyl ligand was bound to the lithium atom as a terminally bound κ1-enamide (8 and 10), a bridging η3-1-azaallyl (6), or a bridging κ1-enamide (5). The stereochemistry about the CC bond was Z for 5, 8 and 10 and E for 7. X-ray data are provided for 5, 6, 7, 8 and 10 and multinuclear NMR spectra data in C6D6 or C6D5CD3 for each of 5-10. 相似文献
30.
J. C.T.R. Burckett St. Laurent P. B. Hitchcock M. A. King H. W. Kroto M. F. Meidine S. I. Klein 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):259-262
Abstract The chemistry of the novel phospha-alkenes RP[dbnd]CR'2, and phospha-alkynes, RC[tbnd]P, containing 2pπ-3pπ bonds is of current interest.1,2 Recent molecular orbital calculations,3,4 suggest that the highest occupied molecular orbital in CH2[dbnd]PH is of the π-type with the phosphorus lone pair ó-orbital only slightly more stable while the π? lumo orbital is relatively low lying. We now report He (I) photoelectron spectroscopic studies on a variety of RC[tbnd]P molecules5,6 which indicate that the homo is also of the π-type and the π-σ separation is much greater than that found in the analogous RC[tbnd]N systems. 相似文献