A new synthetic route to aminophosphines

The reactions of R₂PPR₂ (R = Me, Et, Ph) and (MeP)₅ with Me_3−nAs(NMe₂)_n (n = 1, 2, 3) and of Me₂PPMe₂ with Me₂AsNR′₂ (R′ = Et, Prⁿ, and Prⁱ) were investigated as a function of time at room temperature using ¹H and ³¹P NMR spectroscopy. For the diphosphine/Me₂AsNR′₂ reactions, the NMR spectral data suggest a reaction pathway involving the initial formation of R₂PAsMe₂ and the respective acyclic dialkylaminophosphine, R₂PNR′₂. The P---As intermediate then symmetrizes to R₂PPR₂ and Me₂AsAsMe₂, the parent aminoarsine is completely consumed, and additional R₂PNR′ is formed. The relative rate of aminophosphine production is dependent upon the nature of the substituent on the phosphorus and nitrogen atoms. For systems involving MeAs(NMe₂)₂ and As(NMe₂)₃ as reactants, the intermediates could not be characterized, but the products were the expected aminophosphine and (MeAs)₅ or elemental arsenic, respectively. (MeP)₅ reacts to give MeP(NMe₂)₂ and the expected As---As bonded species. A comparison of the reactivity of these systems with analogous diarsine/aminoarsine systems is discussed. The results of the NMR study were utilized in designing a convenient, high yield, synthetic route to acyclic aminophosphines.     

The tungsten-tungsten triple bond---18. Bridging and terminal allyl ligands in complexes of the formula W2(R)2(NMe2)4, where R = C3H5 and C4H7

The reaction between RMgCl (two equivalents) and 1,2-W₂Cl₂(NMe₂)₄ in hydrocarbon solvents affords the compounds W₂R₂(NMe₂)₄, where R = allyl and 1− and 2-methyl-allyl. In the solid state the molecular structure of W₂(C₃H₅)₂(NMe₂)₄ has C₂ symmetry with bridging allyl ligands and terminal W---NMe₂ ligands. The W---W distance 2.480(1) Å and the C---C distances, 1.47(1) Å, imply an extensive mixing of the allyl π-MOs with the WW π-MOs, and this is supported by an MO calculation on the molecule W₂(C₃H₅)₂(NH₂)₄ employing the method of Fenske and Hall. The most notable interaction is the ability of the (WW)⁶⁺ centre to donate to the allyl π^*-MO (π₃). This interaction is largely responsible for the long W---W distance, as well as the long C---C distances, in the allyl ligand. The structure of the 2-methyl-allyl derivative W₂(C₄H₇)₂(NMe₂)₄ in the solid state reveals a gauche-W₂C₂N₄ core with W---W = 2.286(1) Å and W---C = 2.18(1) Å, typical of WW and W---C triple and single bonds, respectively. In solution (toluene-d₈) ¹H and ¹³C NMR spectra over a temperature range −80°C to +60°C indicate that both anti- and gauche- W₂C₂N₄ rotamers are present for the 2-methyl-allyl derivative. In addition, there is a facile fluxional process that equilibrates both ends of the 2-methyl-allyl ligand on the NMR time-scale. This process leads to a coalescence at 100°C and is believed to take place via an η³-bound intermediate. The 1-methyl-allyl derivative also binds in an η¹ fashion in solution and temperature-dependent rotations about the W---N, W---C and C=C bonds are frozen out at low temperatures. The spectra of the allyl compound W₂(C₃H₅)₂(NMe₂)₄ revealed the presence of two isomers in solution—one of which can be readily reconciled with the presence of the bridging isomer found in the solid state while the other is proposed to be W₂(η³-C₃H₅)₂(NMe₂)₄. The compound W₂R₂(NMe₂)₄ where R = 2,4-dimethyl- pentadiene was similarly prepared and displayed dynamic NMR behaviour explainable in terms of facile η¹ = η³ interconversions.     

Heterogenization of racemic ethylenebis(1-indenyl)zirconium dichloride on trimethylaluminum vapor modified silica surface

Heterogeneous metallocene catalysts were prepared by adsorbing rac-Et(Ind)₂ZrCl₂ on a modified silica surface in solution. The modification of silica was conducted in gas phase with atomic layer chemical vapor deposition (ALCVD) technique, where the silica, preheated at either 350 or 600°C, was allowed to react with vaporized trimethylaluminum (TMA) at 250°C. Modified carriers and heterogeneous catalysts were characterized with FTIR, ¹H MAS (magic-angle spinning) NMR, ¹³C, and ²⁹Si CP (cross-polarization) MAS NMR spectroscopies and elemental analyses. In the reaction of TMA with silica, a saturated surface was formed consisting of different (---O)_4−nSi(CH₃)_n (n=1, 2 or 3) and ---AlCH₃ groups. The ratio of ---SiMe to ---AlMe groups was approximately 1.5 in the TMA/SiO₂ carriers. When the metallocene was adsorbed onto the carrier it seemed to react with the surface ---AlCH₃ groups and possibly ---ZrCH₃ groups were formed. Heterogeneous catalysts were tested in the polymerization of ethylene and propylene in the presence of methylalumoxane (MAO). And they produced similar polymer as the homogeneous rac-Et(Ind)₂ZrCl₂ catalyst, but with lower activity. A catalyst with the best activity was achieved from silica that was preheated at 600°C. Moreover, leaching of catalyst was examined whereupon a part of zirconium was observed to desorb from the carrier.     

Polymerization of ethylene with (C5Me5)2Zr(NMe2)2 cocatalyzed by common alkyl aluminums

Polymerizations of ethylene have been carried out by using Cp₂^*Zr(NMe₂)₂ (Cp^*=C₅Me₅) compound combined with common alkyl aluminums (AlR₃) and methylaluminoxane (MAO) as cocatalysts. The AlMe₃ cocatalyzed system showed no activity due to the formation of stable but inactive heterodinuclear [Cp₂^*2Zr(μ-Me)₂AlMe₂]⁺ cations; however, the bulkier AlR₃ [AlEt₃, Al(i-Bu)₃ and Al(i-Bu)₂H] cocatalyzed systems showed very high activities. Especially, Cp₂^*Zr(NMe₂)₂/Al(i-Bu)₃ catalyst showed higher catalytic activity and produced higher molecular weight (MW) polymer than Cp₂^*Zr(NMe₂)₂/MAO catalyst, demonstrating both MAO and bulky AlR₃ are effective cocatalysts for Cp₂^*Zr(NMe₂)₂ compound.     

Synthesis and structure of ansa-cyclopentadienyl pyrrolyl titanium complexes: [(η-C5H4)CH2(2-C4H3N)]Ti(NMe2)2 and [1,3-{CH2(2-C4H3N)}2(η-C5H3)]Ti(NMe2)

Reaction of ansa-cyclopentadienyl pyrrolyl ligand (C₅H₅)CH₂(2-C₄H₃NH) (2) with Ti(NMe₂)₄ affords bis(dimethylamido)titanium complex [(η⁵-C₅H₄)CH₂(2-C₄H₃N)]Ti(NMe₂)₂ (3) via amine elimination. A cyclopentadiene ligand with two pendant pyrrolyl arms, a mixture of 1,3- and 1,4-{CH₂(2-C₄H₃NH)}₂C₅H₄ (4), undergoes an analogous reaction with Ti(NMe₂)₄ to give [1,3-{CH₂(2-C₄H₃N)}₂(η⁵-C₅H₃)]Ti(NMe₂) (5). Molecular structures of 3 and 5 have been determined by single crystal X-ray diffraction studies.     

双核茂金属催化剂的合成、表征与应用

使用桥连配体锂盐与MCl₄络合, 合成了4个不同结构的双核茂金属化合物[μ,μ-(CH₂)₃]{[C(H)·(η⁵-C₅H₄)(η⁵-C₁₃H₈)](MCl₂)}₂[M=Zr or Ti](4, 5)和[μ,μ-(CH₂)₃]{[C(H)(η⁵-C₅H₄)(η⁵-C₉H₆)]·(MCl₂)}₂[M=Zr or Ti](6, 7), 配体和化合物都经过核磁氢谱(¹H NMR)、 碳谱(¹³C NMR)、 红外光谱(IR)及元素分析等表征, 确认了化学结构. 以甲基铝氧烷(MAO)为助催化剂, 化合物4~7为催化剂催化丙烯聚合, 考察了聚合温度、 乙烯压力、 铝钛或铝锆比对催化剂活性及聚合物分子量的影响. 结果表明, 多亚甲基桥连双核茂金属是高活性乙烯和丙烯聚合催化剂, 乙烯聚合活性最高达到7.5× 10⁶ g PE/(mol Zr·h)(化合物6), 丙烯聚合活性达 10 × 10⁵ g sPP/(mol Zr·h)(化合物4). 所得间规聚丙烯(sPP)的间规度指数(SI, r) 达到90%. 在同样条件下, 双核化合物的催化活性、 聚合物分子量M_w(> 100000)以及分子量分布(MWD>2.5)均比相应的单核化合物高(M_w<70000, MWD≤2), 表明该体系中存在较强的核效应.     

Snthesis and x-ray structure of an isomeric cyclophosphazene complex containing antimony(III)

The monosilylated acyclic phosphazene ligand Me₃SiNP(NMe₂)₂NP(NMe₂)₂ NH₂ (3) has been synthesized and characterized. The reaction of 3 with antimony triacetate, Sb(OOCMe₃), in refluxing toluene forms a cyclic phosphazene derivative, [N{P(NMe₂)₂NH}₂Sb(OOCMe)₂ (4), which is characterized by elemental analyses, mass, IR and NMR spectroscopy and single-crystal X-ray structural analysis. Complex 4 crystallizes in the form of a cis and trans isomeric chain in the solid state.     

Tetrakisdimethylamidozirconium and its dimethylamido lithium adduct: Structures of [zr(nme2)4]2 and zr(nme2)6li2(thf)2

The molecular structure of [Zr(NMe₂)₄]₂ has been determined by an x-ray study and shown to involve a central Zr₂N₈ moiety involving the fusing of two trigonal bipyramidal units along a common axial-equatorial edge. The terminal Zr---NMe₂ units have trigonal planar coordination about the nitrogen atoms: Zr---N = 2.050(5) and 2.104(5) Å, and Zr---N (bridge) = 2.224(3) and 2.453(4) Å for equatorial and axial bonds, respectively. The Zr---Zr distance is 3.704(1) Å as expected for a non-M---M bonding bridged compound. In tetrahydrofuran solution, Zr(NMe₂)₄ and LiNMe₂ react irreversibly giving Zr(NMe₂)₆ Li₂(THF)₂ which has been isolated and characterized by an X-ray study. The central ZrN₆ octahedral moiety is capped on two opposite faces by Li atoms which are also coordinated to an oxygen atom of a THF molecule. Pertinent distances are: Zr---N = 2.22(7) (av.), N---Li = 2.155(25) (av.) and Li---O = 1.915(10) Å.     

The reactivity of dimethylaluminum hydride with the aminoarsines Me2AsNMe2, MeAs(NMe2)2, and As(NMe2)3

The reactions of (Me₂AlH)₃ with Me₂AsNMe₂, MeAs(NMe₂)₂, and As(NMe₂)₃ were investigated as a function of time at room temperature and over the temperature range −90 to 24°C by use of ¹H and ¹³C NMR spectroscopy. (Me₂AlH)₃ was found to be very reactive toward the aminoarsines, even at −90°C, and no stable Me₂AlH-aminoarsine adducts were observed. Instead, the initial stages of the reactions involved AS---N bond cleavage with the generation of highly reactive AlN- and AsH-bonded species. The subsequent course of each reaction and the final arsenic-containing product distribution depended upon the original AL:N stoichiometric ratio and the respective aminoarsine. When the Al:N ratio was 1:1, the reactions were straightforward for each aminoarsine. However, in every case, [Me₂AlNMe₂]₂ was the final AlN-containing product. Independent reactions were carried out to verify many of the proposed decomposition pathways that lead to thermodynamically stable products. The results of this study are compared with those of the analogous, previously reported (Me₃Al)₂-aminoarsine systems. Additionally, a new synthetic route to [Me₂AlAsMe₂]₃ has been established from the reaction of (Me₂AlH)₃ with Me₂AsH.     

Interaction between Pd and Ag on the surface of silica

Palladium, silver and palladium–silver catalysts supported on silica were prepared by coimpregnation of support with solution of AgNO₃ and Pd(NO₃)₂. The catalysts were characterized by X-ray powder diffraction (XRD), temperature programmed reduction (TPR), time of flight ion mass spectrometry (ToF-SIMS), chemisorption of carbon monoxide and were tested in the reaction of selective oxidation of glucose to gluconic acid.

XRD and TPR studies have shown that an interaction between Pd and Ag on the surface of silica after oxidation at 500 °C and reduction at 260 °C leads to the formation of solid solutions.

ToF-SIMS images of the surface of 5% Ag/SiO₂ catalyst after oxidation at 500 °C and reduction at 260 °C show that Ag atoms supported on silica are not distributed homogenously but tend to form regions of enhanced Ag concentration. Positive ions images of the surface of 5% Pd/SiO₂ catalyst also display regions of enhanced concentration of Pd atoms, but they are more homogenously distributed on silica.

ToF-SIMS peak intensity ratio ¹⁰⁸Pd⁺/¹⁰⁷Ag⁺ for bimetallic 5% Pd–5% Ag/SiO₂ catalysts has a lower value than that obtained for physical mixture 5% Pd/SiO₂–5% Ag/SiO₂ which indicates that the surface of bimetallic catalyst is enriched with silver atoms.     

Modified silicas as supports for single-site zirconocene catalysts

The reactivity of Cp₂ZrCl₂ towards partially dehydroxylated silica was evaluated and the effects of chemical modification of this silica were studied. Different modified silicas were prepared by reaction of the original partially dehydroxylated silica with silicon ethers, EtOSiMe₃ and (Me₃Si)₂O, or a silazane, (Me₃Si)₂NH. The resulting materials were activated with MAO and the catalytic systems were evaluated in ethylene polymerization. The different reactions were monitored by FT-IR spectroscopy. The catalysts were characterized by elemental analysis as well as by infrared and UV–vis spectroscopy. Grafting of organosilanes occurs by reaction with reactive siloxane bridges. The new SiR₃ groups formed on the surface react with Cp₂ZrCl₂ to form volatile ClSiMe₃ and oxo zirconium species. These latter species are active, after the addition of MAO, in ethylene polymerization. The effects caused by changing the nature of the modifier in the grafting reaction with the metallocene, as well as the catalytic activities of the resulting materials, are presented and discussed.     

A new dirbenium complex with an unsupported bridging hydride ligand

The reaction of Re₂(CO)₈(μ-H)2 with CH₂(NMe₂)₂ in chloroform at 25°C yielded the new compound Re₂(CO)₈(NHMe₂)(Cl)(μ-H) (1) in 31% yield. Compound 1 was characterized by IR, ¹H NMR and a single-crystal X-ray diffraction analysis. Crystal data: orthorhombic, Pbca, a = 13.787(4), b = 19.884(5), c = 12.296(2) Å. Solution by direct methods (MITHRIL), R = 0.035 for 1800 reflections. The complex contains two rhenium atoms linked by an unsupported hydride bridge, Re Re = 3.362(1) Å, Re(1)---H = 1.8(1) Å and Re(2)---H = 2.0(1) Å. A chloride ligand abstracted from the solvent is terminally bonded to Re(1), and a dimethylamine ligand abstracted from the CH₂(NMe₂)₂ is coordinated to Re(2). When heated to 68°C, the dimethylamine ligand was eliminated and the chloride ligand became a bridge in the new compound Re₂(CO)₈(μ-H)(μ-Cl) (2), yield 76%.     

Synthese und konformationsstudien von selen-analoga der metallocen-dithiolen-chelate früher übergangsmetalle

The reaction of the metallocene dichlorides Cp₂MCl₂ (Cp = η⁵-C₅H₅; M = Ti, Zr, Hf, Mo, W) and Cp₂′TiCl₂ (Cp′ = η⁵-C₅H₄CH₃) with equimolar amounts of dilithium-benzene-o-diselenolate, 1,2-(LiSe)₂C₆H₄, gives the chelate complexes Cp₂M(Se₂C₆H₄) (M = Ti (I), Zr (II), Hf (III), Mo (IV), W (V)) and Cp₂′Ti(Se₂C₆H₄) (VI). CpTiCl₃ reacts with 1,2-(LiSe)₂C₆H₄ to give CpTiCl(Se₂C₆H₄) (VII). The ring inversion activation parameters for I–VI can be determined by means of temperature-dependent ¹H NMR spectroscopy in solution. The fragmentation behaviour of I–VII in the mass spectrometer has been investigated by pursuing metastable transitions, using linked-scan techniques.     

Group 3 and 4 metal alkyl and hydrido complexes containing a linked amido-cyclopentadienyl ligand: “constrained geometry” polymerization catalysts for nonpolar and polar monomers

In order to understand the nature of the putative cationic 12-electron species [M(η⁵:η¹-C₅R₄SiMe₂NR′)R″]⁺ of titanium catalysts supported by a linked amido-cyclopentadienyl ligand, several derivatives with different cyclopentadienyl C₅R₄ and amido substituents R′ were studied systematically. The use of tridentate variants (C₅R₄SiMe₂NCH₂CH₂X)²⁻ (C₅R₄=C₅Me₄, C₅H₄, C₅H₃^tBu; X=OMe, SMe, NMe₂) allowed the NMR spectroscopic observation of the titanium benzyl cations [Ti(η⁵:η¹-C₅Me₄SiMe₂NCH₂CH₂X)(CH₂Ph)]⁺. Isoelectronic neutral rare earth metal complexes [Ln(η⁵:η¹-C₅R₄SiMe₂NR′)R″] can be expected to be active for polymerization. To arrive at neutral 12-electron hydride and alkyl species of the rare earth metals, we employed a lanthanide tris(alkyl) complex [Ln(CH₂SiMe₃)₃(THF)₂] (Ln=Y, Lu, Yb, Er, Tb), which allows the facile synthesis of the linked amido-cyclopentadienyl complex [Ln(η⁵:η¹-C₅Me₄SiMe₂NCMe₃)(CH₂SiMe₃)(THF)]. Hydrogenolysis of the linked amido-cyclopentadienyl alkyl complex leads to the dimeric hydrido complex [Ln(η⁵:η¹-C₅Me₄SiMe₂NCMe₃)(THF)(μ-H)]₂. These complexes are single-site, single-component catalysts for the polymerization of ethylene and a variety of polar monomers such as acrylates and acrylonitrile. Nonpolar monomers such as -olefins and styrene, in contrast, give isolable mono-insertion products which allow detailed studies of the initiation process.     

Synthesis, characterization and catalytic application of SBA-15 immobilized rare earth metal sandwiched polyoxometalates

Rare earth metal sandwiched Keggin-type heteropolyoxometalates, K₁₁[RE(PW₁₁O₃₉)₂] (RE–PW₁₁, RE = La, Ce, Pr, Nd, Sm, Eu, Dy and Y), were anchored onto aminosilylated mesoporous silica SBA-15 and the resulting RE–PW₁₁/APTS/SBA-15 materials were characterized by ICP, FT-IR, XRD, N₂ adsorption, ³¹P MAS NMR and TEM. The RE–PW₁₁ clusters preserve their structure in the surface-modified mesopores. The catalytic activity of RE–PW₁₁ clusters was tested on heterogeneous oxidation of cyclohexene by H₂O₂. The interaction between RE–PW₁₁ and amino groups grafted on the channel surface of SBA-15 leads to strong immobilization of RE–PW₁₁ due to the introduction of the rare earth metal centre, which is against the leaching during the reaction.     

Influence of the solvent and of the counteranion on the structure of silyl cations stabilized by a terdentate aryldiamine ligand

Solution NMR studies of silyl cations [ArSiMe₂]⁺X⁻ (X = I, CF₃SO₃) incorporating the terdentate aryl diamine ligand Ar - C₆H₃₋ 2,6-(CH₂NMe₂)₂ have been carried out in a protic solvent (methanol-d₄) and in an aprotic solvent (CD₂Cl₂). This study has shown that the structure of these silyl cations is highly dependent on the solvent. In CD₂Cl₂, the silyl cation is five-coordinated owing to the coordination of one NMe₂ group and of the anion to the silicon centre which gives rise to a dissymmetric structure. On the other hand, in CD₃OD there is no coordination of the anion, but the silyl cation is also probably five-coordinated due to the coordination of the solvent to the silicon atom which is supported by the X-ray analysis of the compound 9. With the weakly nucleophilic anion BPh₄⁻ in CD₂Cl₂, in addition to the silyl cation previously described, another five-coordinated silyl cation resulting from the coordination of both NMe₂ groups to the Si centre was postulated.     

Synthesis and crystal structure of a germanium(II) calix[6]arene containing unusual diamidosilyl ether groups

The reaction of Ge[N(SiMe₃)₂]₂ with calix[6]arene furnishes a novel macrocyclic product having two divalent germanium atoms incorporated into a Ge₂NO rhombus which contains a μ₂-oxygen atom and a μ₂-NH₂ group. The crystal structure of the product indicates the presence of a conformationally rigid molecule where three of the six oxygen atoms of the calix[6]arene are bound to the germanium atoms while the remaining three have been converted into –OSiMe₃ or unusual –OSi(H)(NH₂)₂ groups. Spectral (¹H, ¹³C, and ²⁹Si NMR) data in solution are consistent with the solid-state structure and indicate the germanium calix[6]arene retains its structure in solution.     

New Half-sandwich Zirconium（IV） Complexes Containing Salicylaldimine Ligands： Synthesis,Characterizations and Catalytic Properties

Two new half-sandwich zirconium（IV） complexes bearing salicylaldimine ligands of the type Cp＊Zr[2-tBu-4-R-6-（CH=NiPr）C6H2O]C12[R=H（1）, tBu（2）] were prepared by the reaction of Cp＊ZrC13 with the corresponding lithium of salicylaldimine ligands 2-tBu-4-R-6-（CH=NiPr）C6H2OLi[R=H（LiLa）, tBu（LiLb）]. Com- plexes 1 and 2 were characterized by 1H NMR, BC NMR spectroscopy and elemental analysis. When activated with AliBu3 and Ph3CB（C6F5）4, both complexes 1 and 2 exhibited reasonable catalytic activities for ethylene polymeriza- tion, producing polyethylenes with moderate molecular weight. Complexes 1 and 2 also exhibited reasonable catalyt- ic activities for ethylene copolymerization with 1-hexene, producing poly（ethylene-co-l-hexene）s with moderate molecular weight and reasonable 1-hexene content.     

A spectroscopic study on the 12-heteropolyacids of molybdenum and tungsten (H3PMo12−nWnO40) combined with cetylpyridinium bromide in the epoxidation of cyclopentene

The epoxidation of cyclopentene with hydrogen peroxide catalyzed by 12-heteropolyacids of molybdenum and tungsten (H₃PMo_12−nW_nO₄₀, n = 1–11), 12-tungstophosphoric acid and 12-molybdophosphoric acid combined with cetylpyridinium bromide as a phase transfer reagent was carried out in acetonitrile. Among 13 heteropolyacids investigated, catalyst of H₃PMo₆W₆O₄₀ showed the highest activity, giving a conversion of 60% and a selectivity of 95% in the epoxidation of cyclopentene. The fresh catalysts and the catalysts under reaction condition were characterized by UV–vis, FT-IR and ³¹P NMR spectroscopy, which has revealed that all of the molybdotungstophosphoric acids were degraded in the presence of hydrogen peroxide to form a considerable amount of phosphorus-containing species. The active species resulted from H₃PMo₆W₆O₄₀ are new kinds of phosphorus-containing species, which is different from {PO₄[WO(O₂)₂]₄}³⁻.     

顺式二氯二氨合铂与核苷作用的13C核磁共振研究

本文用¹³C NMR法系统研究了溶液中顺式二氯二氨合铂与胸苷、胞苷、鸟苷和5'-腺嘌呤单核苷酸的作用,确定了不同条件下形成配合物的组成及其分子申铂原子与配体的成键方式。在中性介质中顺铂分别与胸苷、胞苷作用,生成N₃配位的顺-[Pt(NH₃)₂(ThyH_-1)₂]和顺-[Pt(NH₃)₂(Cyt)₂]²⁺;与鸟苷随摩尔比不同相应生成顺-[Pt(NH₃)₂(N₂-Guo)₂]²⁺和[Pt(NH₃)₂(N₂,N₁-GuoH_-1)]_nⁿ⁺,当pH=3和摩尔比为1时,尚有微量[Pt(NH₃)₂(N₇,O(C₆)Guo)]²⁺生成;在中性介质中顺铂与5'-AMP亦随摩尔比不同,生成顺-[Pt(NH₃)₂(N₇-5'-AMP)₂]^2-或兼生成顺-[Pt(NH₃)₂(N₇,N₁-5'-AMP)]_n。根据所得结果讨论了顺铂抗癌作用机制,提出了顺铂可能与DNA同一链上相邻二个鸟嘌呤基上的N₇N₁键合形成链内交联的新机制。