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1.
《Polyhedron》1999,18(26):3559-3565
A novel mixed-ligand complex ZnPhen(i-Pr2NCS2)2 has been synthesized and its single crystals grown. We have determined its crystal structure from X-ray diffraction data. The structure consists of monomeric molecules; a zinc atom surrounded by two nitrogen and four sulfur atoms making a distorted octahedron. Various packing modes of molecules forming isolated ‘dimers’, ribbons (chains), columns and layers have emerged from the study of the spatial molecule arrangement in the complexes ZnPhen(R2NCS2)2 (R=Me, Et, i-Pr, n-Pr, i-Bu, n-Bu). The interactions between the Phen molecules have also been studied for these complexes.  相似文献   

2.
The use of differential scanning calorimetry has provided enthalpies,H (298 K), of the dissociation reactions RCo(salen) (pyridine) (c) RCo(salen) (c)+pyridine(g)R=Me 34.5, Et 21.9,n-Pr 12.8,i-Pr 11.1,n-Bu 8.3 andi-Bu 13.5 kJ mol–1
Zusammenfassung Mit Hilfe der Differential-Scanning-Kalorimetrie wurden die EnthalpienH(298 K) der Dissoziationsreaktionen RCo(salen)(Pyridin)(c) RCo(saleo)(c)+Pyridin(g) bestimmt: R=Me 34,5, Et 21,9,n-Pr 12,8,i-Pr 11,1,n-Bu 8,3 undi-Bu 13,5 kJ·mol–1.

(298 K) : R() () R ()+() R R = – 34,5; – 21,9; - –12,8; - 11,1; - –8,3 13,5 · –1.
  相似文献   

3.
The Reactions of tBu2P–P=P(Me)tBu2 and (Me3Si)tBuP–P=P(Me)tBu2 with PR3 tBu2P–P=P(Me)tBu2 ( 1 ) reacts at 20 °C with PMe3, PEt3, P(c‐Hex)3, P(p‐Tol)3, PPh2Me, PPh2Et, PPhEt2, PPh2iPr, PPh3 and P(NEt2)3 yielding tBu2P–P=PR3 and tBu2PMe; however, PtBu3, PtBu2(SiMe3) and tBu2PCl don't. tBu2PH and 1 form tBu2P–PH–PtBu2 which yields tBu2P–P=PEt3 when treated with PEt3. Ph2PH, tBuPH2, PH3, Ph2PCl and EtOH don't substitute the tBu2PMe group in 1 , instead, the molecule is decomposed. With PEt3, (Me3Si)tBuP–P=P(Me)tBu2 forms (Me3Si)tBuP–P=PEt3. The compounds tBu2P–P=PR3 decompose at 20 °C to different degrees giving P‐rich consecutive products of the phosphinophosphinidene.  相似文献   

4.
tBu2P–PLi–PtBu2 · 2THF reacts with [(R3P)2MCl2] (M = Pt, Pd, Ni; R3P = Et3P, pTol3P, Ph2EtP, iPr3P) to yield isomers of [(1,2‐η‐tBu2P=P–PtBu2)M(PR3)Cl], in which the tBu2P–P–PtBu2 ligand adopts the arrangement of a side‐on bonded 1,1‐di‐tert‐butyl‐2‐(di‐tert‐butylphosphanyl)diphosphenium cation. tBu2P–PLi–P(NEt2)2 · 2THF reacts with [(R3P)2MCl2] but does not form complexes with a tBu2P–P–P(NEt2)2 moiety, however, splitting of a P–P(NEt2)2 bond of the parent triphosphane takes place.  相似文献   

5.
Coote ML  Pross A  Radom L 《Organic letters》2003,5(24):4689-4692
[structure: see text] High level ab initio molecular orbital calculations confirm experimental indications that the effect of alkyl substituents (R = Me, Et, i-Pr, t-Bu) on R-X bond dissociation energies varies considerably according to the nature of X. A simple qualitative explanation in terms of valence-bond theory is presented, highlighting the increasing importance of the stabilization of R-X by the ionic R(+)X(-) configuration for electronegative X substituents (such as F, OH, and OCH(3)).  相似文献   

6.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXII. The Formation of [η2‐{tBu–P=P–SiMe3}Pt(PR3)2] from (Me3Si)tBuP–P=P(Me)tBu2 and [η2‐{C2H4}Pt(PR3)2] (Me3Si)tBuP–P = P(Me)tBu2 reacts with [η2‐{C2H4}Pt(PR3)2] yielding [η2‐{tBu–P=P–SiMe3}Pt(PR3)2]. However, there is no indication for an isomer which would be the analogue to the well known [η2‐{tBu2P–P}Pt(PPh3)2]. The syntheses and NMR data of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] and [η2‐{tBu–P=P–SiMe3}Pt(PMe3)2] as well as the results of the single crystal structure determination of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] are reported.  相似文献   

7.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXIII. Reactions of tBu2P–P=P(Me)tBu2 with (Et3P)2NiCl2 and [{η2‐C2H4}Ni(PEt3)2] tBu2P–P=P(Me)tBu2 ( 1 ) forms with (Et3P)2NiCl2 ( 2 ) and Na(Nph) the [μ‐(1,3 : 2,3‐η‐tBu2P4tBu2){Ni(PEt3)Cl}2] ( 3 ) as main product. Using Na/Hg instead as reducing agent the Ni0 compounds [{η2tBu2P–P}Ni(PEt3)2] ( 4 ), [{η2tBu2P–P=P–PtBu2}Ni(PEt3)2] ( 5 ) and [(Et3P)Ni(μ‐PtBu2)]2 ( 6 ) with four‐membered Ni2P2 ring result. [{η2‐C2H4}Ni(PEt3)2] yields with 1 also 4 . The compounds were characterized by 1H and 31P{1H} NMR investigations and 3 also by a single crystal X‐ray analysis. It crystallizes triclinic in the space group P 1 with a = 1129.4(2), b = 1256.8(3), c = 1569.5(3) pm, α = 72.44(3)°, β = 70.52(3)° and γ = 74.20(3)°.  相似文献   

8.
The Phosphides LiR2P7, Li2RP7 (R = Me3Si, Et, iPr, iBu) as well as Mixed Alkylated and Silylated Heptaphosphanes(3) Formation and properties of LiR2P7 and Li2PR7 (R = Me3Si, Et, iPr, iBu) and their reactions with Me3SiCl or alkylhalides yielding mixed alkylated and silylated heptaphosphanes(3) are reported. Reactions of (Me3Si)3P7 and Li3P7. 3 DME produce mixtures of Li(Me3Si)3P7, Li2(Me3Si)P7 and Li3P7 from which pure Li(Me3Si)2P7 (s, as) can be isolated by means of an extraction with toluene. Similarly, the isomers of LiR2P7 (R = Et, iPr, iBu) can be extracted from the mixtures obtained by reacting Li3P7 with alkylbromides. The (s) isomers of LiR2P7 in solution at about 20°C from the (as) isomers whereas the latter up to 70°C do not show any inversion. The (as) lithiumdialkylphosphides can be obtained as ether free products (red brown powder, isoluble in toluene, soluble in THF) by repeated addition of toluene and removal of the solvents; the (s) isomers decompose during the procure. In reactions of LiEt2P7. THF (s, as) in toluene at ?30°C with EtBr only the (s) isomer is substituted and gives Et3P7 (s), however on warming to 20°C by inversion of Pe a ratio of (s) : (as( = 1 : 3 is obtained. With Li(iBu)2P7, (s) reaction begins above ?20°C the giving both the (s) and the (as) isomer. (iBu)3P7 (s) is the prefered isomer at higher temperatures. Li(Me3Si)2P7 (s, as) with Me3SiCl exclusively yields (Me3Si)3P7 (s). Li2RP7 (R = alkyl, Me3SI) is not available. From mixtures with LiR2P7 and Li3P7, it can be isolated only after repeated cumbersome extraction of LiR2P7 as was shown with Li2(iPr)P7 as an example. Ether free LiEt2P7(s, as) with Me3SiCl exclusively gives Et2(Me3Si)P7 (s, as) whereas LiEt2P7 ? THF due to its THF content does not. Similarly, ether free Li(iBu)2P7 yields (iBu)2(Me3Si)P7 (s, as). The compounds R(Me3Si)2P7 (R = alkyl) cannot be selectively prepared neither starting from Li2RP7 with Me3SiCI) nor from Li(Me3Si)2P7 with RX. Such, the reaction of Li(Me3Si)2P7 ? THF with EtBr in toluene at ?78°C yield a mixture of Et(Me3Si)2P7 (42%), Et2(Me3Si)P7 (27010), (Me3Si)3P7 (29%) and Et3P7 (2%). (Me3Si)3P7 with MeI in a molar ratio of 1 : 1 at 70°C quantitatively produces Me(Me3Si)2P7 whereas already using a molar ratio of 1 : 2 also Me3P7 is obtained. With EtBr mixtures of Et(Me3Si)2P7 and Et3P7 are formed. iBuBr gives iBu3P7, but tBuBr does not yield any tBu3P7.  相似文献   

9.
The triphosphanes RMe(2)SiCH(2)P(PR'(2))(2) (R = Me, Ph; R' = SiMe(3), Cy) are synthesised in good yield via metathesis of organodichlorophosphanes and LiPR'(2), while for R' = Ph a propensity to form (Ph(2)P)(2) precludes isolation of the in situ characterised triphosphanes. Where R = Me and R' = SiMe(3) the triphosphane has also been characterised by single crystal X-ray diffraction and exhibits a single geometric conformer in the solid state, though solution-phase NMR spectra are indicative of facile conformational exchange across a wide temperature range. All of the described triphosphanes exhibit comparable behaviour, with their respective (31)P{(1)H} NMR spectra manifesting anomalous 'second-order' characteristics, which are considered using full spin-Hamiltonian simulation. Preliminary studies of coordination chemistry and ancillary reactivity of the triphosphanes are described.  相似文献   

10.
Formation of Cyclic Silylphosphanes. Reaction of Li-Phosphides with R2SiCl2 (R? Me, Et, t-Bu) The reaction of Me2SiCl2 with Li-phosphides (mixture of LiPH2, Li2PH) leads to the formation of Me2Si(PH2)Cl 1 , Me2Si(PH2)2 2 , H2P? SiMe2? PH? SiMe2Cl 3 , (H2P? SiMe2)2PH 4 , (HP? SiMe2)3 6 , 5 , 7 , 8 , 9 , 10 , 40 . Excess of phosphides in Et2O – as well as excess of LiPH2 – favourably forms 10 . Li2PH (virtually free of Li3P and LiPH2) is obtained by reaction of LiPH2 · DME with LiBu; Li3P by reaction of PH3 with LiBu in toluene. Isomerization by Li/H migration determines the course of reaction of the PH-bearing compounds with Li-phosphides. With Me2SiCl2 Li3P mainly generates compound 10 . The reaction of the Li-phosphides with Et2SiCl2 mainly leads to (HP? SiEt2)3 18 and (HP? SiEt2)2 17 as well as to Et2Si(PH2)Cl 11 , Et2Si(PH2)2 12 , (ClEt2Si)2PH 13 , H2P? SiEt2? PH? SiEt2Cl 14 , (H2P? SiEt2)2PH 15 and 16 . In the reaction with LiPH2 · DME the same compounds are obtained and isomerization by Li/H migration (formation of PH3) already begins at ?70°C. In toluene ClEt2Si? P(SiEt2)2P? SiEt2Cl is additionally formed. Derivatives of 9, 10, 40 are not observed. The reaction of (t-Bu)2SiCl2 with LiPH2 leads to HP[Si(t-Bu)2]2PH 20 (yield 76%) and formation of PH3, the reaction with Li2PH to 20 (54%) besides HP[Si(t-Bu)2]2PLi 21 .  相似文献   

11.
Contributions to the Chemistry of Phosphorus. 117. Synthesis and Properties of the Hexaorganyl-octaphosphanes(6) P8R6, R = Me, Et, Pri The Hexaorganyl-octaphosphanes(6) P8Me6 ( 1 ), P8Et6 ( 2 ), and P8Pr ( 3 ) have been obtained by reacting mixtures of the corresponding organyldichlorophosphanes and phosphorus(III) chloride with magnesium. In the case of 1 and 2 the organyl-cyclophosphanes (PR)n can also be used in the reaction with phosphorus(III) chloride and magnesium. Besides, mainly P7R5 as well as other polycyclic organylphosphanes are formed. 2 and 3 have been isolated as pure substances, whereas 1 was concentrated to ?50 mol-% in the product mixture. According to their 31P-NMR spectra the three compounds possess a pentalane-analogous P8-skeleton with the substituents within each five-membered ring in trans position and the substituents of different five-membered rings next to the zero bridge in cis position; the organyl groups in the 3, 7 position are trans oriented with respect to the free electron pairs of the bridgehead atoms. Therefore, the structures of 1 – 3 differ from the known tert-butyl compound P8Bu, whereas the corresponding phosphorus hydride P8H6 has the same pentalane-analogous P8-skeleton, thus being a bicyclo[3.3.0]octaphosphane.  相似文献   

12.
Formation and Reactions of the CH2Li‐Derivatives of tBu2P–P=P(CH3)tBu2 and (Me3Si)tBuP–P=P(CH3)tBu2 With nBuLi, (Me3Si)tBuP–P=P(CH3)tBu2 ( 1 ) and tBu2P–P=P(CH3)tBu2 ( 2 ) yield (Me3Si)tBuP–P=P(CH2Li)tBu2 ( 3 ) and tBu2P–P=P(CH2Li)tBu2 ( 4 ), wich react with Me3SiCl to give (Me3Si)tBuP–P=P(CH2–SiMe3)tBu2 ( 5 ) and tBu2P–P=P(CH2–SiMe3)tBu2 ( 6 ), respectively. With tBu2P–P(SiMe3)–PtBuCl ( 7 ), compound 3 forms 5 as well as the cyclic products [H2C–P(tBu)2=P–P(tBu)–PtBu] ( 8 ) and [H2C–P(tBu)2=P–P(PtBu2)–P(tBu)] ( 9 ). Also 3 forms 8 with tBuPCl2. The cleavage of the Me3Si–P‐bond in 1 by means of C2Cl6 or N‐bromo‐succinimide yields (Cl)tBuP–P=P(CH3)tBu2 ( 10 ) or (Br)tBuP–P=P(CH3)tBu2 ( 11 ), resp. With LiP(SiMe3)2, 10 forms (Me3Si)2P–P(tBu)–P=P(CH3)tBu2 ( 12 ), and Et2P–P(tBu)–P=P(CH3)tBu2 ( 13 ) with LiPEt2. All compounds are characterized by 31P NMR Data and mass spectra; the ylide 5 and the THF adduct of 4 additionally by X‐ray structure analyses.  相似文献   

13.
Phosphine or phosphonium iodide react with boron triiodide in CS2 or benzene to form the adduct H3P–BI3. The water-sensitive white solid is thermally stable up to ~150°C. Its IR and NMR spectrum are recorded.  相似文献   

14.
15.
Influence of the Ring Atoms on the Structure of Triel‐Pentel Heterocycles – Synthesis and X‐Ray Crystal Structures of [Me2InAs(SiMe3)2]2 and [Me2InSb(SiMe3)2]3 Triel‐pentel heterocycles [Me2InE(SiMe3)2]x have been prepared by dehalosilylation reactions from Me2InCl and E(SiMe3)3 (E = As, x = 2; E = Sb, x = 3) and characterised by NMR spectroscopy and by X‐ray crystal structure analyses. In addition the X‐ray crystal structures of [Me2GaAs(SiMe3)2]2 and [Me2InP(SiMe3)2]2 are reported. The compounds complete a family of 13 identically substituted heterocycles [Me2ME(SiMe3)2]x (M = Al, Ga, In; E = N, P, As, Sb, Bi; x = 2, 3), whose structures were investigated depending on the ring atoms M and E. The tendencies that have been observed concerning the ring sizes can be explained by the interplay of the atomic radii of the central atoms and the sterical demand of the ligands. After a formal separation of the M–E bonds in σ bonds and dative bonds the characteristic differences and trends in the endocyclic and exocyclic bond angles of both centres M and E can be interpreted on the basis of a simple Lewis acid/base adduct model.  相似文献   

16.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XVIII. Syntheses and Structures of [{η2tBu2P–P=P–PtBu2}Pt(PR3)2] tBu2P–P=P(Me)tBu2 reacts with [{η2‐C2H4} · Pt(PR3)2] as well as with [{η2tBu2P–P}Pt(PR3)2] yielding [{η2tBu2P–P=P–PtBu2}Pt(PR3)2]; PR3 = PMe3 3 a , PEtPh2 3 b , 1/2 dppe 3 c , PPh3 3 d , P(p‐Tol)3 3 e . All compounds are characterized by 1H and 31P NMR spectra, for 3 b and 3 d also crystal structure determinations were performed. 3 b crystallizes in the triclinic space group P1 (No. 2) with a = 1212.58(7), b = 1430.74(8), c = 1629.34(11) pm, α = 77.321(6), β = 70.469(5), γ = 87.312(6)°. 3 d crystallizes in the triclinic space group P1 (No. 2) with a = 1122.60(9), b = 1355.88(11), c = 2025.11(14) pm, α = 83.824(9), β = 82.498(9), γ = 67.214(8)°.  相似文献   

17.
Formation of the Cyclotetraphosphanes cis- und trans-P4(SiMe3)2(CMe3)2 in the Reaction of (Me3C)PCl2 with LiP(SiMe3)2 · 2 THF The mechanism of the reaction of (Me3C)PCl2 1 with LiP(SiMe3)2 · 2 THF 2 was investigated. With a mole ration of 1:1 at ?60°C quantitatively (Me3C)(Cl)P? P(SiMe3)2 3 is formed. This compound eliminates Me3SiCl on warming to 20°C, yielding Me3Si? P?P? CMe3 4 (can be trapped using 2,3-dimethyl-1,3-butadiene in a 4+2 cycloaddition), which dimerizes to produce the cyclotetraphosphanes cis-P4(SiMe3)2(CMe3)2 5 and trans-P4(SiMe3)2(CMe3)2 6 . Also with a mole ratio of 1:2 initially 3 is formed which remarkably slower reacts on to give [(Me3Si)2P]P2P? CMe3 8 . Remaining LiP(SiMe3)2 cleaves one Si? P bond of 8 producing (Me3)2P? P(CMe3)? P(SiMe3)2Li. Via a condensation to the pentaphosphide 10 and an elimination of LiP(SiMe3)2 from this intermediate, eventually trans-P4(SiMe3)2(CMe3)2 6 is obtained as the exclusive cyclotetra-phosphane product.  相似文献   

18.
tBu2P–PLi–PtBu2·2THF reacts with [cis‐(Et3P)2MCl2] (M = Ni, Pd) yielding [(1,2‐η‐tBu2P=P–PtBu2)Ni(PEt3)Cl] and [(1,2‐η‐tBu2P=P–PtBu2)Pd(PEt3)Cl], respectively. tBu2P– PLi–PtBu2 undergoes an oxidation process and the tBu2P–P–PtBu2 ligand adopts in the products the structure of a side‐on bonded 1,1‐di‐tert‐butyl‐2‐(di‐tert‐butylphosphino)diphosphenium cation with a short P–P bond. Surprisingly, the reaction of tBu2P–PLi–PtBu2·2THF with [cis‐(Et3P)2PtCl2] does not yield [(1,2‐η‐tBu2P=P–PtBu2)Pt(PEt3)Cl].  相似文献   

19.
Phosphanediyl Transfer from Inversely Polarized Phosphaalkenes R1P=C(NMe2)2 (R1 = tBu, Cy, Ph, H) onto Phosphenium Complexes [(η5‐C5H5)(CO)2M=P(R2)R3] (R2 = R3 = Ph; R2 = tBu, R3 = H; R2 = Ph, R3 = N(SiMe3)2) Reaction of the freshly prepared phosphenium tungsten complex [(η5‐C5H5)(CO)2W=PPh2] ( 3 ) with the inversely polarized phosphaalkenes RP=C(NMe2)2 ( 1 ) ( a : R = tBu; b : Cy; c : Ph) led to the η2‐diphosphanyl complexes ( 9a‐c ) which were isolated by column chromatography as yellow crystals in 24‐30 % yield. Similarly, phosphenium complexes [(η5‐C5H5)(CO)2M=P(H)tBu] (M = W ( 6 ); Mo ( 8 )) were converted into (M = W ( 11 ); Mo ( 12 )) by the formal abstraction of the phosphanediyl [PtBu] from 1a . Treatment of [(η5‐C5H5)(CO)2W=P(Ph)N(SiMe3)2] ( 4 ) with HP=C(NMe2)2 ( 1d ) gave rise to the formation of yellow crystalline ( 10 ). The products were characterized by elemental analyses and spectra (IR, 1H, 13C‐, 31P‐NMR, MS). The molecular structure of compound 10 was elucidated by an X‐ray diffraction analysis.  相似文献   

20.
Synthesis and Crystal Structure of the Spirocycle [(i-Pr)2P(S)NSiMe3]2SnCl2 The reaction of (i-Pr)2P(S)N(SiMe3)2 ( 1 ) with SnCl4 in 2:1 ratio yields under elimination of ClSiMe3 the four-membered spirocycle [(i-Pr)2P(S)NSiMe3]2SnCl2 ( 2 ). The molecular structure of 2 was investigated by an X-ray structure analysis. Compound 2 crystallises in the monoclinic space group P21, Z = 2, a = 938.1(1), b = 1 424.1(2), c = 1 207.2(1) pm, β = 110.59(1)°, R = 2.05% for 4 102 reflexions. Compound 2 is a spirocycle with two Sn? N? P? S-rings joined at tin. The two rings are in cis-position.  相似文献   

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