首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The selective functionalization of the polyphosphorus moiety Ph2PCH2PPh2PPPP present as a tetrahapto‐ligand in complex [Ir(dppm)(Ph2PCH2PPh2PPPP)]+ ( 1 , dppm=Ph2PCH2PPh2) was obtained by reaction of 1 with water under basic conditions at room temperature. The formation of the new triphosphaallyl moiety η3‐P3{P(O)H} was determined in solution by NMR spectroscopy, and confirmed in the solid state by a single‐crystal X‐ray structure of the stable product [Ir(κ2‐dppm)(κ1‐dppm)(η3‐P3{P(O)H})] ( 2 ). In solution, 2 has a fluxional behavior attributable to the four P atoms belonging to the tetraphosphorus moiety in 1 and exhibits a chemical exchange process involving the two PPh2 moieties of the same bidentate ligand, as determined by 1D and 2D NMR spectroscopy experiments carried out at variable temperature. The mechanism of the reaction was investigated at the DFT level, which suggested a selective attack of an in‐situ generated OH? anion on one of the non‐coordinated phosphorus atoms of the P4 moiety. The reaction then evolves through an acid‐assisted tautomerization, which leads to the final compound 2 . Bonding analysis pointed out that the new unsubstituted P3‐unit in the η3‐P3{P(O)H} moiety behaves as a triphosphallyl ligand.  相似文献   

2.
The reactivity of the hydrolysis product of hexaphenylcarbodiphosphorane, PPh3CHP(O)Ph2, towards different soft Lewis acids, such as CuI and Ag[BF4] are reported. While CuI exclusively binds at the ylidic carbon atom, reaction of the silver cation in CH2Cl2 leads to proton abstraction from the solvent to give the cation [PPh3CH2P(O)Ph2]+. Surprisingly, Ag+ replaces the methyl group of [PPh3CHMeP(O)Ph2]+ to produce a dimeric complex, in which Ag+ is coordinated to C and O forming an eight membered ring. The compounds were characterized by spectroscopic methods and X‐ray diffraction.  相似文献   

3.
Abstract

The anion Ph2P? (K+, 18-crown-6) reacts with t-BuHgCl in HMPA to form Ph2PCMe3 by a free radical chain mechanism. In Me2SO, Ph2P(O)CMe3 is produced. Reaction of Ph2P? with PhCOCH2HgCl yields the oxidative dimerization product isolable from HMPA but readily converted to Ph2P(O)P(O)Ph2 in Me2SO.  相似文献   

4.
A study regarding coordination chemistry of the bis(diphenylphosphino)amide ligand Ph2P‐N‐PPh2 at Group 4 metallocenes is presented herein. Coordination of N,N‐bis(diphenylphosphino)amine ( 1 ) to [(Cp2TiCl)2] (Cp=η5‐cyclopentadienyl) generated [Cp2Ti(Cl)P(Ph2)N(H)PPh2] ( 2 ). The heterometallacyclic complex [Cp2Ti(κ2P,P‐Ph2P‐N‐PPh2)] ( 3 Ti ) can be prepared by reaction of 2 with n‐butyllithium as well as from the reaction of the known titanocene–alkyne complex [Cp2Ti(η2‐Me3SiC2SiMe3)] with the amine 1 . Reactions of the lithium amide [(thf)3Li{N(PPh2)2}] with [Cp2MCl2] (M=Zr, Hf) yielded the corresponding zirconocene and hafnocene complexes [Cp2M(Cl){κ2N,P‐N(PPh2)2}] ( 4 Zr and 4 Hf ). Reduction of 4 Zr with magnesium gave the highly strained heterometallacycle [Cp2Zr(κ2P,P‐Ph2P‐N‐PPh2)] ( 3 Zr ). Complexes 2 , 3 Ti , 4 Hf , and 3 Zr were characterized by X‐ray crystallography. The structures and bondings of all complexes were investigated by DFT calculations.  相似文献   

5.
Six new complexes of tin(IV) halides with phosphorus‐containing ligands have been fully characterized by single‐crystal X‐ray diffraction at low temperature. Three of the compounds, derived from the diphosphanes bis‐(diphenylphosphino)methane or bis‐(dicyclohexylphosphino)methane, have a novel zwitterionic structure, with five Cl ligands and one unidentate phosphorus‐containing ligand on tin, together with a proton on the second phosphorus atom of the potentially bidentate ligand; these are Cl5SnP(Ph2)CH2PPh2H+ ( 1 ), Cl5SnOP(Ph2)CH2‐PPh2H+ ( 2 ), and Cl5SnOP(cy2)CH2Pcy2H+ ( 3 ). The other three complexes have a bidentate donor attached to the SnX4 moiety; they comprise Cl4SnOP(Ph2)‐(CH2)2PPh2O ( 4 ), a derivative of bis‐(diphenylphosphino)ethane dioxide, I4SnOP(Ph2)CH2PPh2O ( 5 ), a similar derivative of bis‐(diphenylphosphino)‐methane dioxide, and the very unusual Br4SnAs‐(Ph2)(CH2)2PPh2O ( 6 ), with coordination to tin by As and O. Since the starting material for the last compound was Ph2As(CH2)2PPh2, this result illustrates well the more facile oxidation of P(III) than As(III). © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:136–143, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20525  相似文献   

6.
The new symmetrical diphosphonium salt [Ph2P(CH2)2PPh2(CH2C(O)C6H4Br)2] Br2 ( S ) was synthesized in the reaction of 1,2‐bis (diphenylphosphino) ethane (dppe) and related ketone. Further treatment with NEt3 gave the symmetrical α‐keto stabilized diphosphine ylide [Ph2P(CH2)2PPh2(CHC(O)C6H4Br)2] ( Y 1 ). The unsymmetrical α‐keto stabilized diphosphine ylide [Ph2P(CH2)2PPh2(CHC(O)C6H4Br)] ( Y 2 ) was synthesized in the reaction of diphosphine in 1:1 ratio with 2.3′‐dibromoacetophenone, then treatment with NEt3. The reaction of dibromo (1,5‐cyclooctadiene)palladium (II), [PdBr2(COD)] with this ligand ( Y 1 ) in equimolar ratio gave the new C,C‐chelated [PdBr2(Ph2P(CH2)2PPh2(C(H)C(O)C6H4Br)2)] ( 1 ) and with unsymmetrical phosphorus ylide [Ph2P(CH2)2PPh2C(H)C(O)C6H4Br] ( Y 2 ) gave the new P, C‐chelated palladacycle complex [PdBr2(Ph2P(CH2)2PPh2C(H)C(O)Br)] ( 2 ). These compounds were characterized successfully by FT‐IR, NMR (1H, 13C and 31P) spectroscopic methods and the crystal structure of Y 1 and 2 were elucidated by single crystal X‐ray diffraction. The results indicated that the complex 1 was C, C‐chelated whereas complex 2 was P, C‐chelated. These air/moisture stable complexes were employed as efficient catalysts for the Mizoroki‐Heck cross‐coupling reaction of several aryl chlorides, and the Taguchi method was used to optimize the yield of Mizoroki‐Heck coupling. The optimum condition was found to be as followed: base; K2CO3, solvent; DMF and loading of catalyst; 0.005 mmol.  相似文献   

7.
8.
The intermolecular radical functionalization of arenes with aryl and alkyl H‐phosphinate esters, as well as diphenylphosphine oxide and H‐phosphonate diesters, is described. The novel catalytic MnII/excess MnIV system is a convenient and inexpensive solution to directly convert Csp2?H into C?P bonds. The reaction can be employed to functionalize P‐stereogenic H‐phosphinates since it is stereospecific. With monosubstituted aromatics, the selectivity for para‐substitution increases in the order (RO)2P(O)H<R1P(O)(OR)H<Ph2P(O)H, a trend that may be explained by steric effects.  相似文献   

9.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes XXI The Influence of the PR3 Ligands on Formation and Properties of the Phosphinophosphinidene Complexes [{η2tBu2P–P}Pt(PR3)2] and [{η2tBu2P1–P2}Pt(P3R3)(P4R′3)] (R3P)2PtCl2 and C2H4 yield the compounds [{η2‐C2H4}Pt(PR3)2] (PR3 = PMe3, PEt3, PPhEt2, PPh2Et, PPh2Me, PPh2iPr, PPh2tBu and P(p‐Tol)3); which react with tBu2P–P=PMetBu2 to give the phosphinophosphinidene complexes [{η2tBu2P–P}Pt(PMe3)2], [{η2tBu2P–P}Pt(PEt3)2], [{η2tBu2P–P}Pt(PPhEt2)2], [{η2tBu2P–P}Pt(PPh2Et)2], [{η2tBu2P–P}Pt(PPh2Me)2], [{η2tBu2P–P}Pt(PPh2iPr], [{η2tBu2P–P}Pt(PPh2tBu)2] and [{η2tBu2P–P}Pt(P(p‐Tol)3)2]. [{η2tBu2P–P}Pt(PPh3)2] reacts with PMe3 and PEt3 as well as with tBu2PMe, PiPr3 and P(c‐Hex)3 by substituting one PPh3 ligand to give [{η2tBu2P1–P2}Pt(P3Me3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3Ph3)(P4Me3)], [{η2tBu2P1–P2}Pt(P3Et3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3MetBu2)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3iPr3)(P4Ph3)] and [{η2tBu2P1–P2}Pt(P3(c‐Hex)3)(P4Ph3)]. With tBu2PMe, [{η2tBu2P–P}Pt(P(p‐Tol)3)2] forms [{η2tBu2P1–P2}Pt(P3MetBu2)(P4(p‐Tol)3)]. The NMR data of the compounds are given and discussed with respect to the influence of the PR3 ligands.  相似文献   

10.
A study of the coordination chemistry of different bis(diphenylphosphino)methanide ligands [Ph2PC(X)PPh2] (X=H, SiMe3) with Group 4 metallocenes is presented. The paramagnetic complexes [Cp2Ti{κ2P,P‐Ph2PC(X)PPh2}] (X=H ( 3 a ), X=SiMe3 ( 3 b )) have been prepared by the reactions of [(Cp2TiCl)2] with [Li{C(X)PPh2}2(thf)3]. Complex 3 b could also be synthesized by reaction of the known titanocene alkyne complex [Cp2Ti(η2‐Me3SiC2SiMe3)] with Ph2PC(H)(SiMe3)PPh2 ( 2 b ). The heterometallacyclic complex [Cp2Zr(H){κ2P,P‐Ph2PC(H)PPh2}] ( 4 aH ) has been prepared by reaction of the Schwartz reagent with [Li{C(H)PPh2}2(thf)3]. Reactions of [Cp2HfCl2] with [Li{C(X)PPh2}2(thf)3] gave the highly strained corresponding metallacycles [Cp2M(Cl){κ2P,P‐Ph2PC(X)PPh2}] ( 5 aCl and 5 bCl ) in very good yields. Complexes 3 a , 4 aH , and 5 aCl have been characterized by X‐ray crystallography. Complex 3 a has also been characterized by EPR spectroscopy. The structure and bonding of the complexes has been investigated by DFT analysis. Reactions of complexes 4 aH , 5 aCl , and 5 bCl did not give the corresponding more unsaturated heterometallacyclobuta‐2,3‐dienes.  相似文献   

11.
Abstract

The diphosphine dioxides Ph2P (O) CH2P (O)Ph2.(I, Ph2P(O)CH2CH2P(O)Ph2 (II), Ph2P(O)CH=CHP(O)Ph2-cis (III), -trans (IV), [Ph2P(O)] C=CH (V), [Ph2P(O) 12C=PPh3 (VI), and also non-symmetric Ph2(P)OCH=CHP(O)PhEt-trans (VII), Et2P(O)CH=CHP(O)PhEt-trans (VIII), have been studied in CH2C12 and CHCl3 solutions by means of 13C and 31P NMR.  相似文献   

12.
The aminophosphane ligand 1‐amino‐2‐(diphenylphosphanyl)ethane [Ph2P(CH2)2NH2] reacts with dichloridotris(triphenylphosphane)ruthenium(II), [RuCl2(PPh3)3], to form chloridobis[2‐(diphenylphosphanyl)ethanamine‐κ2P,N](triphenylphosphane‐κP)ruthenium(II) chloride toluene monosolvate, [RuCl(C18H15P)(C14H16NP)2]Cl·C7H8 or [RuCl(PPh3){Ph2P(CH2)2NH2}2]Cl·C7H8. The asymmetric unit of the monoclinic unit cell contains two molecules of the RuII cation, two chloride anions and two toluene molecules. The RuII cation is octahedrally coordinated by two chelating Ph2P(CH2)2NH2 ligands, a triphenylphosphane (PPh3) ligand and a chloride ligand. The three P atoms are meridionally coordinated, with the Ph2P– groups from the ligands being trans. The two –NH2 groups are cis, as are the chloride and PPh3 ligands. This chiral stereochemistry of the [RuCl(PPh3){Ph2P(CH2)2NH2}2]+ cation is unique in ruthenium–aminophosphane chemistry.  相似文献   

13.
Reactions of the oxorhenium(V) complexes [ReOX3(PPh3)2] (X = Cl, Br) with the N‐heterocyclic carbene (NHC) 1,3,4‐triphenyl‐1,2,4‐triazol‐5‐ylidene (LPh) under mild conditions and in the presence of MeOH or water give [ReOX2(Y)(PPh3)(LPh)] complexes (X = Cl, Br; Y = OMe, OH). Attempted reactions of the carbene precursor 5‐methoxy‐1,3,4‐triphenyl‐4,5‐dihydro‐1H‐1,2,4‐triazole ( 1 ) with [ReOCl3(PPh3)2] or [NBu4][ReOCl4] in boiling xylene resulted in protonation of the intermediately formed carbene and decomposition products such as [HLPh][ReOCl4(OPPh3)], [HLPh][ReOCl4(OH2)] or [HLPh][ReO4] were isolated. The neutral [ReOX2(Y)(PPh3)(HLPh)] complexes are purple, airstable solids. The bulky NHC ligands coordinate monodentate and in cis‐position to PPh3. The relatively long Re–C bond lengths of approximate 2.1Å indicate metal‐carbon single bonds.  相似文献   

14.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XX Formation and Structure of [{η2tBu2P–P}Pt(PHtBu2)(PPh3)] [{η2tBu2P1–P2}Pt(P3Ph3)(P4Ph3)] ( 2 ) reacts with tBu2PH exchanging only the P3Ph3 group to give [{η2tBu2P1–P2}Pt(P3HtBu2)(P4Ph3)] ( 1 ). The crystal stucture determination of 1 together with its 31P{1H} NMR data allow for an unequivocal assignment of the coupling constants in related Pt complexes. 1 crystallizes in the triclinic space group P1 (no. 2) with a = 1030.33(15), b = 1244.46(19), c = 1604.1(3) pm, α = 86.565(17)°, β = 80.344(18)°, γ = 74.729(17)°.  相似文献   

15.
A series of palladium complexes ( 2a–2g ) ( 2a : [6‐tBu‐2‐PPh2‐C6H3O]PdMe(Py); 2b : [6‐C6F5–2‐PPh2‐C6H3O]PdMe(Py); 2c : [6‐tBu‐2‐PPhtBu‐C6H3O]PdMe(Py); 2d : [2‐PPhtBu‐C6H4O] PdMe(Py); 2e : [6‐SiMe3–2‐PPh2‐C6H3O]PdMe(Py); 2f : [2‐tBu‐6‐(Ph2P=O)‐C6H3O]PdMe(Py); 2g : [6‐SiMe3–2‐(Ph2P=O)‐C6H3S]PdMe(Py)) bearing phosphine (oxide)‐(thio) phenolate ligand have been efficiently synthesized and characterized. The solid‐state structures of complexes 2d , 2f and 2g have been further confirmed by single‐crystal X‐ray diffraction, which revealed a square‐planar geometry of palladium center. In the presence of B(C6F5)3, these complexes can be used as catalysts to polymerize norbornene (NB) with relatively high yields, producing vinyl‐addition polymers. Interestingly, 2a /B(C6F5)3 system catalyzed the polymerization of NB in living polymerization manner at high temperature (polydispersity index 1.07, Mn up to 1.5 × 104). The co‐polymerization of NB and polar monomers was also studied using catalysts 2a and 2f . All the obtained co‐polymers could dissolve in common solvent.  相似文献   

16.
Carbon monoxide causes elimination of the hetero-allene molecules ptolNNptol and PhNCO in Rh(PPh3)2[Ph2PC(Nptol)Nptol] and Rh(PPh3)2[Ph2PC(NPh)O], respectively. The resulting complex in both cases is [Rh(CO)2(PPh2)(PPh2)]n.In the reaction of RhCl(PPh3)3 with Ph2P(S)C(Nptol)NHptol or Ph2P(S)C(O)NHPh in the presence of a base, a similar elimination occurs yielding the liberated heterocumulene and Rh(PPh3)2(SPPh2). This complex is the first example of a specieswith a side-on coordinated Ph2PS-moiety. We have also prepared this compound and other species, containing η2SPPh2, via direct interaction of RhCl(PPh3)3 and IrCl(PPh3)2(C8H14) with Ph2P(S)H. Upon reaction with CO, the chelating PPh2 group is displaced by CO to give complexes with an end-on coordinated Ph2PS? ligand.Finally, Rh(PPh3)2(SPPh2) incorporates three moles of PhNCS, one by insertion and two by disproportionation, to yield Rh(PPh3)(PhNC)(PhNCS2)[Ph2P(S)C(S)NPh].  相似文献   

17.
The phosphorus ylids Ph3PCHR (R = Me, Et, Prn, Pri, Bun, Cl, and OMe), and the ylids Ph3AsCH2, Me2SCH2, and Me2S(O)CH2 react with [Ni(η5-C5H5)Br(PPh3)] at room temperature to give the complexes [Ni(Ph3PCHR)(η5-C5H5(PPh3)] Br, [Ni(Ph3AsCH2)(η5-C5H5)(PPh3)]Br, [Ni(Me2SCH2)(η5-C5H5)(PPh3)]Br and [Ni{Me2S(O)CH2} (η5-C5H5)(PPh3)]Br, respectively. These are readily converted into the corresponding hexafluorophosphate salts on reaction with ammonium hexafluorophosphate. Under more forcing conditions the stabilised ylid Ph3PCHCOPh gives a product believed to be the complex [Ni(Ph3PCHCOPh)25-C5H5)]Br, isolated and characterised as its PF6? salt.  相似文献   

18.
Low‐temperature generation of P‐nitroxyl phosphane 2 (Ph2POTEMP), which was obtained by the reaction of Ph2PH ( 1 ) with two equivalents of TEMPO, is presented. Upon warming, phosphane 2 decomposed to give P‐nitroxyl phosphane P‐oxide 3 (Ph2P(O)OTEMP) as one of the final products. This facile synthetic protocol also enabled access to P‐sulfide and P‐borane derivatives 7 and 13 , respectively, by using Ph2P(S)H ( 6 ) or Ph2P(BH3)H ( 11 ) and TEMPO. Phosphane sulfide 7 revealed a rearrangement to phosphane oxide 8 (Ph2P(O)STEMP) in CDCl3 at ambient temperature, whereas in THF, thermal decomposition of sulfide 7 yielded salt 10 ([TEMP‐H2][Ph2P(S)O]). As well as EPR and detailed NMR kinetic studies, indepth theoretical studies provided an insight into the reaction pathways and spin‐density distributions of the reactive intermediates.  相似文献   

19.
Bismuth diphenylphosphanides Bi(NONR)(PPh2) (NONR=[O(SiMe2NR)2], R=tBu, 2,6‐iPr2C6H3, Aryl) undergo facile decomposition via single‐electron processes to form reduced Bi and P species. The corresponding derivatives Bi(NONR)(PCy2) are stable. Reaction of the isolated BiII radical .Bi(NONAr) with white phosphorus (P4) proceeds with the reversible and selective activation of a single P?P bond to afford the bimetallic μ,η1:1‐bicyclo[1.1.0]tetraphosphabutane compound.  相似文献   

20.
The PPh2P(S)NHP(S)PPh2 (dppaS2) ligand reacts with the starting complexes PtCl2(L-L) (L-L = Ph2PCH2PPh2), (dppm), Ph2PCH2CH2PPh2 (dppe), Ph2PCH2CH2CH2PPh2 (dppp), and NaClO4·H2O. Final products are monomeric complexes, and their formulas are [Pt(L-L)(dppaS2-H)] [(L-L = dppm(1), dppe(2), dppp(3)]. All of these have been characterized by 1H, 13C,31{P1H} NMR, FTIR, and elemental analysis. These complexes were also examined by TGA, DTA, and DSC analysis. Complexes 2 and 3 were crystallographically characterized.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号