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 890 毫秒
1.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXIV. Formation and Structure of [μ‐(1,2 : 2‐η‐tBu2P–P){Mo(CO)2cp′}2] [cp′Mo(CO)2]2 (cp′ = C5H4tBu) reacts with tBu2P–P=P(Me)tBu2 to yield the compound [μ‐(1,2 : 2‐η‐tBu2P–P){Mo(CO)2cp′}2], which crystallizes in the space group P212121 with a = 1202.42(7), b = 1552.48(8), and c = 1765.3(1) pm.  相似文献   

2.
Heterobinuclear Complexes: Synthesis and X‐ray Crystal Structures of [RuRh(μ‐CO)(CO)4(μ‐PtBu2)(tBu2PH)], [RuRh(μ‐CO)(CO)3(μ‐PtBu2)(μ‐Ph2PCH2PPh2)], and [CoRh(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)] [Ru3Rh(CO)73‐H)(μ‐PtBu2)2(tBu2PH)(μ‐Cl)2] ( 2 ) yields by cluster degradation under CO pressure as main product the heterobinuclear complex [RuRh(μ‐CO)(CO)4(μ‐PtBu2)(tBu2PH)] ( 4 ). The compound crystallizes in the orthorhombic space group Pcab with a = 15.6802(15), b = 28.953(3), c = 11.8419(19) Å and V = 5376.2(11) Å3. The reaction of 4 with dppm (Ph2PCH2PPh2) in THF at room temperature affords in good yields [RuRh(μ‐CO)(CO)3(μ‐PtBu2)(μ‐dppm)] ( 7 ). 7 crystallizes in the triclinic space group P 1 with a = 9.7503(19), b = 13.399(3), c = 15.823(3) Å and V = 1854.6 Å3. Moreover single crystals of [CoRh(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)] ( 9 ) could be obtained and the single‐crystal X‐ray structure analysis revealed that 9 crystallizes in the monoclinic space group P21/a with a = 11.611(2), b = 13.333(2), c = 18.186(3) Å and V = 2693.0(8) Å3.  相似文献   

3.
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   

4.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XIX. [Co4P2(PtBu2)2(CO)8] and [{Co(CO)3}2P4tBu4] from Co2(CO)8 and tBu2P–P=P(Me)tBu2 Co2(CO)8 reacts with tBu2P–P=P(Me)tBu2 yielding the compounds [Co4P2(PtBu2)2(CO)8] ( 1 ) and [{η2tBu2P=P–P=PtBu2}{Co(CO)3}2] ( 2 a ) cis, ( 2 b ) trans. In 1 , four Co and two P atoms form a tetragonal bipyramid, in which two adjacent Co atoms are μ2‐bridged by tBu2P groups. Additionally, two CO groups are linked to each Co atom. In 2 a and 2 b , each of the Co(CO)3 units is η2‐coordinated to the terminal P2 units resulting in the cis‐ and trans‐configurations 2 a and 2 b . 1 crystallizes in the orthorhombic space group Pnnm (No. 58) with a = 879,41(5), b = 1199,11(8), c = 1773,65(11) pm. 2 a crystallizes in the monoclinic space group P21/n (No. 14) with a = 875,97(5), b = 1625,36(11), c = 2117,86(12) pm, β = 91,714(7)°. 2 b crystallizes in the triclinic space group P 1 (No. 2) with a = 812,00(10), b = 843,40(10), c = 1179,3(2) pm, α = 100,92(2)°, β = 102,31(2)°, γ = 102,25(2)°.  相似文献   

5.
Activation of Carbon Disulfide on Triruthenium Clusters: Synthesis and X‐Ray Crystal Structure Analysis of [Ru3(CO)5(μ‐H)2(μ‐PCy2)(μ‐Ph2PCH2PPh2){μ‐η2‐PCy2C(S)}(μ3‐S)] and [Ru3(CO)5(CS)(μ‐H)(μ‐PtBu2)(μ‐PCy2)23‐S)] [Ru3(CO)6(μ‐H)2(μ‐PCy2)2(μ‐dppm)] ( 1 ) (dppm = Ph2PCH2PPh2) reacts under mild conditions with CS2 and yields by oxidative decarbonylation and insertion of CS into one phosphido bridge the opened 50 VE‐cluster [Ru3(CO)5(μ‐H)2(μ‐PCy2)(μ‐dppm){μ‐η2‐PCy2C(S)}(μ3‐S)] ( 2 ) with only two M–M bonds. The compound 2 crystallizes in the triclinic space group P 1 with a = 19.093(3), b = 12.2883(12), c = 20.098(3) Å; α = 84.65(3), β = 77.21(3), γ = 81.87(3)° and V = 2790.7(11) Å3. The reaction of [Ru3(CO)7(μ‐H)(μ‐PtBu2)(μ‐PCy2)2] ( 3 ) with CS2 in refluxing toluene affords the 50 VE‐cluster [Ru3(CO)5(CS)(μ‐H)(μ‐PtBu2)(μ‐PCy2)23‐S)] ( 4 ). The compound cristallizes in the monoclinic space group P 21/a with a = 19.093(3), b = 12.2883(12), c = 20.098(3) Å; β = 104.223(16)° and V = 4570.9(10) Å3. Although in the solid state structure one elongated Ru–Ru bond has been found the complex 4 can be considered by means of the 31P‐NMR data as an electron‐rich metal cluster.  相似文献   

6.
[Fe2sb‐CO)(CO)3(NO)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)]: Synthesis, X‐ray Crystal Structure and Isomerization Na[Fe2(μ‐CO)(CO)6(μ‐PtBu2)] ( 1 ) reacts with [NO][BF4] at —60 °C in THF to the nitrosyl complex [Fe2(CO)6(NO)(μ‐PtBu2)] ( 2 ). The subsequent reaction of 2 with phosphanes (L) under mild conditions affords the complexes [Fe2(CO)5(NO)L(μ‐PtBu2)], L = PPh3, ( 3a ); η‐dppm (dppm = Ph2PCH2PPh2), ( 3b ). In this case the phosphane substitutes one carbonyl ligand at the iron tetracarbonyl fragment in 2 , which was confirmed by the X‐ray crystal structure analysis of 3a . In solution 3b loses one CO ligand very easily to give dppm as bridging ligand on the Fe‐Fe bond. The thus formed compound [Fe2(CO)4(NO)(μ‐PtBu2)(μ‐dppm)] ( 4 ) occurs in solution in different solvents and over a wide temperature range as a mixture of the two isomers [Fe2sb‐CO)(CO)3(NO)(μ‐PtBu2)(μ‐dppm)] ( 4a ) and [Fe2(CO)4(μ‐NO)(μ‐PtBu2)(μ‐dppm)] ( 4b ). 4a was unambiguously characterized by single‐crystal X‐ray structure analysis while 4b was confirmed both by NMR investigations in solution as well as by means of DFT calculations. Furthermore, the spontaneous reaction of [Fe2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 5 ) with NO at —60 °C in toluene yields a complicated mixture of products containing [Fe2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 6 ) as main product beside the isomers 4a and 4b occuring in very low yields.  相似文献   

7.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXVI. Formation and Structure of [{ cyclo ‐P4(PtBu2)4}{Ni(CO)2}2] [{cyclo‐P4(PtBu2)4}{Ni(CO)2}2] is formed by reaction of the cyclotetraphosphane P4(PtBu2)4 with [Ni(CO)4]. Each Ni(CO)2 unit is coordinated by two adjacent tBu2P groups forming two five‐membered P4Ni rings above and below the planar cyclotetraphosphane ring, respectively. The compound crystallizes in the triclinic space group P 1 (No. 2) with a = 893.29(5), b = 1140.75(7), c = 1235.52(8) pm, α = 109.179(7), β = 100.066(7), γ = 97.595(7)° and Z = 1.  相似文献   

8.
Coordinatively Unsaturated Diiron Complexes: Synthesis and Crystal Structures of [Fe2(CO)4(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] and [Fe2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] [Fe2(μ‐CO)(CO)6(μ‐H)(μ‐PtBu2)] ( 1 ) reacts spontaneously with dppm (dppm = Ph2PCH2PPh2) to give [Fe2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 2 c ). By thermolysis or photolysis, 2 c loses very easily one carbonyl ligand and yields the corresponding electronically and coordinatively unsaturated complex [Fe2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 3 ). 3 exhibits a Fe–Fe double bond which could be confirmed by the addition of methylene to the corresponding dimetallacyclopropane [Fe2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 4 ). The reaction of 1 with dppe (Ph2PC2H4PPh2) affords [Fe2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppe)] ( 5 ). In contrast to the thermolysis of 2 c , yielding 3 , the heating of 5 in toluene leads rapidly to complete decomposition. The reaction of 1 with PPh3 yields [Fe2(CO)6(H)(μ‐PtBu2)(PPh3)] ( 6 a ), while with tBu2PH the compound [Fe2(μ‐CO)(CO)5(μ‐H)(μ‐PtBu2)(tBu2PH)] ( 6 b ) is formed. The thermolysis of 6 b affords [Fe2(CO)5(μ‐PtBu2)2] and the degradation products [Fe(CO)3(tBu2PH)2] and [Fe(CO)4(tBu2PH)]. The molecular structures of 3 , 4 and 6 b were determined by X‐ray crystal structure analyses.  相似文献   

9.
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   

10.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXV. Formation and Structure of [{ cyclo ‐P3(PtBu2)3}{Ni(CO)2}{Ni(CO)3}] tBu2P–P=P(R)tBu2 (R = Br, Me) reacts with [Ni(CO)4] yielding [{cyclo‐P3(PtBu2)3}{Ni(CO)2}{Ni(CO)3}]. The two cistBu2P substituents of the cyclotriphosphane, which results from the trimerization of the phosphinophosphinidene tBu2P–P, are coordinating to a Ni(CO)2 unit forming a five‐membered P4Ni chelate ring. The transtBu2P group is linked to a Ni(CO)3 unit. The compound crystallizes in the orthorhombic space group Pbca (No. 61) with a = 933.30(5), b = 2353.2(1) and c = 3474.7(3) pm.  相似文献   

11.
Coordinatively Unsaturated Diruthenium Complexes: Synthesis and X‐ray Crystal Structures of [Ru2(CO)n(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] (n = 4; 5) and [Ru2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] The reaction of [Ru2(μ‐CO)(CO)5(μ‐H)(μ‐PtBu2)(tBu2PH)] ( 2 ) with dppm yields the dinuclear species [Ru2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 3 ) (dppm = Ph2PCH2PPh2). Under thermal or photolytic conditions 3 loses very easily one carbonyl ligand and affords the corresponding electronically and coordinatively unsaturated complex [Ru2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 4 ). 4 is also obtainable by an one‐pot synthesis from [Ru3(CO)12], an excess of tBu2PH and stoichiometric amounts of dppm via the formation of [Ru2(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)2] ( 1 ). 4 exhibits a Ru–Ru double bond which could be confirmed by addition of methylene to the dimetallacyclopropane [Ru2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 5 ). The molecular structures of 3 , 4 and 5 were determined by X‐ray crystal structure analyses.  相似文献   

12.
Coordinatively Unsaturated Diruthenium Complexes: Synthesis and X‐ray Crystal Structures of [Ru2(CO)3L(μ‐η1 : η2‐C≡CPh)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] (L = CO, PnBu3) [Ru2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 1 ) reacts with several phosphines (L) in refluxing toluene under substitution of one carbonyl ligand and yields the compounds [Ru2(CO)3L(μ‐H)(μ‐PtBu2)(μ‐dppm)] (L = PnBu3, 2 a ; L = PCy2H, 2 b ; L = dppm‐P, 2 c ; dppm = Ph2PCH2PPh2). The reactivity of 1 as well as the activated complexes 2 a – c towards phenylethyne was studied. Thus 1 , 2 a and 2 b , respectively, react with PhC≡CH in refluxing toluene with elimination of dihydrogen to the acetylide‐bridged complexes [Ru2(CO)4(μ‐η1 : η2‐C≡CPh)(μ‐PtBu2)(μ‐dppm)] ( 3 ) and [Ru2(CO)3L(μ‐η1 : η2‐C≡CPh)(μ‐PtBu2)(μ‐dppm)] ( 4 a and 4 b ). The molecular structures of 3 and 4 a were determined by crystal structure analyses.  相似文献   

13.
Coordination Chemistry of P-rich Phosphanes and Silylphosphanes. XVI [1] Reactions of [g2-{P–PtBu2}Pt(PPh3)2] and [g2-{P–PtBu2}Pt(dppe)] with Metal Carbonyls. Formation of [g2-{(CO)5M · PPtBu2}Pt(PPh3)2] (M = Cr, W) and [g2-{(CO)5Cr · PPtBu2}Pt(dppe)] [η2-{P–PtBu2}Pt(PPh3)2] 4 reacts with M(CO)5 · THF (M = Cr, W) by adding the M(CO)5 group to the phosphinophosphinidene ligand yielding [η2-{(CO)5Cr · PPtBu2}Pt(PPh3)2] 1 , or [η2-{(CO)5W · PPtBu2}Pt(PPh3)2] 2 , respectively. Similarly, [η2-{P–PtBu2}Pt(dppe)] 5 yields [η2-{(CO)5Cr · PPtBu2}Pt(dppe)] 3 . Compounds 1 , 2 and 3 are characterized by their 1H- and 31P-NMR spectra, for 2 and 3 also crystal structure determinations were performed. 2 crystallizes in the monoclinic space group P21/n (no. 14) with a = 1422.7(1) pm, b = 1509.3(1) pm, c = 2262.4(2) pm, β = 103.669(9)°. 3 crystallizes in the triclinic space group P1 (no. 2) with a = 1064.55(9) pm, b = 1149.9(1) pm, c = 1693.2(1) pm, α = 88.020(8)°, β = 72.524(7)°, γ = 85.850(8)°.  相似文献   

14.
Reaction of a new type of bidentate ligand PhPQu [PhPQu = 2‐diphenylphosphino‐4‐methylquinoline] with Fe(CO)5 in butanol gave trans‐Fe(FpPQu‐P)(CO)3 (1). Compound 1, which can act as a neutral tridentate organometallic ligand, was reacted with I B, II B metal compounds and a rhodium complex to give six binuclear complexes with Fe? M bonds, Fe(CO)3 (μ‐Ph2PQu)MXn (2–7) [M= Zn(II), Cd(II), Hg(II), Cu(I), Ag(I), Rh(I)], and an ion‐pair complex [Fe(CO)3 (μ‐Ph2PQu)2HgI][HgI3]? (8). The structure of 8 was determined by X‐ray crystallography. Complex 8 crystallizes in the space group P‐1 with a = 1.0758(3), b = 1.6210(4), c=1.7155(4)nm; a=75.60(2), β=71.81(2), γ=81.78(2)° and Z = 2 and its structure was refined to give agreement factors of R=0.050 and Rw = 0.057. The Fe‐Hg bond distance is 0.2536nm.  相似文献   

15.
Coordinatively Unsaturated Diruthenium Complexes: Synthesis and X‐Ray Crystal Structures of [Ru2(CO)4(μ‐H)(μ‐S)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)], [Ru2(CO)4(μ‐X)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] (X = Cl, S2CH) [Ru2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 1 ) reacts in benzene with elemental sulfur to the addition product [Ru2(CO)4(μ‐H)(μ‐S)(μ‐PtBu2)(μ‐dppm)] ( 2 ) (dppm = Ph2PCH2PPh2). 2 is also obtained by reaction of 1 with ethylene sulfide. The reaction of 1 with carbon disulfide yields with insertion of the CS2 into the Ru2(μ‐H) bridge the dithioformato complex [Ru2(CO)4(μ‐S2CH)(μ‐PtBu2)(μ‐dppm)] ( 3 ). Furthermore, 1 reacts with [NO][BF4] to the complex salt [Ru2(CO)4(μ‐NO)(μ‐H)(μ‐PtBu2)(μ‐dppm)][BF4] ( 4 ), and reaction of 1 with CCl4 or CHCl3 affords spontaneously [Ru2(CO)4(μ‐Cl)(μ‐PtBu2)(μ‐dppm)] ( 5 ) in nearly quantitative yield. The molecular structures of 2 , 3 and 5 were confirmed by crystal structure analyses.  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.
Synthesis and Crystal Structure of [C(NMe2)3]2[(CO)4Fe(μ‐InCl2)2Fe(CO)4] Treatment of [C(NMe2)3]2[(CO)4FeInCl3] ( 1 ) with hot water produces the dinuclear complex [C(NMe2)3]2[(CO)4Fe(μ‐InCl2)2Fe(CO)4] ( 2 ) which could be crystallized from dichloromethane/pentane. 2 crystallizes in the monoclinic space group P21/n with a = 835.7(1), b = 1187.8(1), c = 1902.7(1) pm, β = 91.877(5)° and Z = 2. The anion contains a four‐membered Fe—In—Fe—In ring with octahedral environment at the iron atom and tetrahedral coordination at the In atom.  相似文献   

18.
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   

19.
The Crystal Structure of tBu2P? P?P(Br)tBu2 tBu2P? P?P(Br)tBu2 1 crystallizes in the monoclinic space group P21/c with a = 2 888.9(3), b = 972.16(10), c = 1 534.04(14) pm, β = 105.129(8)° and 8 formula units in the unit cell. The two independent P3-units in 1 form angles of 105.77° or 105.98°, resp. One P? P distance (220,4 pm) corresponds to a single bond, the other one (207.9 pm) to a double bond.  相似文献   

20.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XVII [1] [Co(g5‐Me5C5)(g3tBu2PPCH–CH3)] from [Co(g5‐Me5C5)(g2‐C2H4)2] and tBu2P–P=P(Me)tBu2 [Co(η5‐Me5C5)(η3tBu2PPCH–CH3)] 1 is formed in the reaction of [Co(η5‐Me5C5)(η2‐C2H4)2] 2 with tBu2P–P 4 (generated from tBu2P–P=P(Me)tBu2 3 ) by elimination of one C2H4 ligand and coupling of the phosphinophosphinidene with the second one. The structure of 1 is proven by 31P, 13C, 1H NMR spectra and the X‐ray structure analysis. Within the ligand tBu2P1P2C1H–CH3 in 1 , the angle P1–P2–C1 amounts to 90°. The Co, P1, P2, C1 atoms in 1 look like a „butterfly”︁. The reaction of 2 with a mixture of tBu2P–P=P(Me)tBu2 3 and tBu–C?P 5 yields [Co(η5‐Me5C5){η4‐(tBuCP)2}] 6 and 1 . While 6 is spontaneously formed, 1 appears only after complete consumption of 5 .  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