1-(Bis-trimethylsilanyl-methyl)-2,2-dimethyl-propylideneamine | 284674-94-8

• 分子结构分类: 有机化合物 - 有机氮化合物
• 英文名称: 1-(Bis-trimethylsilanyl-methyl)-2,2-dimethyl-propylideneamine
• 英文别名: 3,3-Dimethyl-1,1-bis(trimethylsilyl)butan-2-imine；3,3-dimethyl-1,1-bis(trimethylsilyl)butan-2-imine
• CAS: 284674-94-8
• 化学式: C₁₂H₂₉NSi₂
• mdl: MFCD01632578
• 分子量: 243.54
• InChiKey: KNFKVWSSVOLVHY-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.32
• 重原子数：
  15
• 可旋转键数：
  4
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.916
• 拓扑面积：
  23.8
• 氢给体数：
  1
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  carbanide,cyclopenta-1,3-diene,titanium(4+) 、 1-(Bis-trimethylsilanyl-methyl)-2,2-dimethyl-propylideneamine 以 甲苯 为溶剂， 以40%的产率得到
  参考文献：
  名称：

  The Mechanism of Methane Elimination in B(C₆F₅)₃-Initiated Monocyclopentadienyl-Ketimide Titanium and Related Olefin Polymerization Catalysts

  摘要：

  A new class of monocyclopentadienyl titanium olefin polymerization catalysts and their activation with B(C6F5)(3) is reported herein. Dichlorides Cp[Bu-t(R)C=N]TiCl2 {Cp = C5H5, R = Bu-t (1a); Cp = C5Me5, R = Bu-t (2a); Cp = C5Me4SiMe3, R = Bu-t (3a); Cp = C5Me5, R = CH2SiMe3 (4a); Cp = C5Me5, R = Me (5a)} were prepared in 50-92% yield from CpTiCl3 and Bu-t(R)C=NLi. Analogous dimethyl compounds 1b-5b were prepare via methylation of dichlorides a using MeMgBr in 89-92% yield. Dimethyl compound 6b (L = C5Me5, R = CH(SiMe3)(2)) was prepared directly from Cp*TiMe3 and Bu-t[(Me3Si)(2)CH]C=NH in 40% yield. Dynamic H-1 NMR studies showed that the ketimide ligands in compounds b rotate rapidly about Ti-N on the NMR time scale, with a a Delta G(double dagger) of 9.6(6) kcal mol(-1) or less. The mixed alkyl compound Cp*-[Bu-t(R)C=N]Ti(CH3)CH2SiMe3 {R = (t)3u (7)} was prepared via alkylation of the corresponding methyl chloride derivative with BrMgCH2SiMe3. When treated with B(C6F5)(3), compounds 1b-6b are rapidly converted into the ion pairs {Cp[Bu-t(R)C=N]TiCH3}(+)[H3C(B(C6F5)(3)](-), 1c-6c; mixed alkyl compound 7 yields the ion pair [Cp*((Bu2C)-Bu-t=N)TiCH2SiMe3](+)[H3C(B(C6F5)(3)](-), 7c, exclusively. Multinuclear NMR experiments show that ion pairing is tight in these compounds and that ketimide ligand rotation is occurring with a slightly higher barrier in comparison to the neutral derivatives b. Ion pairs 1c-5e undergo a decomposition process involving loss of methane and producing the neutral compounds Cp[Bu-t(R)C=N]Ti(C6F5)[CH2B(C6F5)(2)], 1d-5d. The X-ray crystal structure of Id has been determined. Active cationic compounds are not regenerated from neutral compounds d in the presence of B(C6F5)(3) and thus this reaction is a potential deactivation pathway for these particular ion pairs. Detailed kinetic studies on the decomposition of 2c show the reaction to be first order in [2c] with activation parameters of Delta H-double dagger = 20.6(8) kcal mol(-1) and Delta S-double dagger = -8.5(10) eu, corresponding to Delta G(298)(double dagger) of 23.1(8) kcal mol(-1). A substantial kinetic isotope effect of k(H)/k(D) = 9.1(6) was measured using d(6)-2c. Further mechanistic experiments, including crossover and examination of alkane elimination from mixed alkyl ion pair 7c, point to a sigma-bond metathesis mechanism for the production of compounds d. The implications of our results for other, related catalyst systems are discussed.

  DOI：

  10.1021/ja994378c
• 作为产物：
  描述：

  [1-(Bis-trimethylsilanyl-methyl)-2,2-dimethyl-prop-(E)-ylidene]-trimethylsilanyl-amine 在 hydrochloric acid diethyl ether 作用下， 以 乙醚 为溶剂， 反应 0.5h， 生成 1-(Bis-trimethylsilanyl-methyl)-2,2-dimethyl-propylideneamine
  参考文献：
  名称：

  The Mechanism of Methane Elimination in B(C₆F₅)₃-Initiated Monocyclopentadienyl-Ketimide Titanium and Related Olefin Polymerization Catalysts

  摘要：

  A new class of monocyclopentadienyl titanium olefin polymerization catalysts and their activation with B(C6F5)(3) is reported herein. Dichlorides Cp[Bu-t(R)C=N]TiCl2 {Cp = C5H5, R = Bu-t (1a); Cp = C5Me5, R = Bu-t (2a); Cp = C5Me4SiMe3, R = Bu-t (3a); Cp = C5Me5, R = CH2SiMe3 (4a); Cp = C5Me5, R = Me (5a)} were prepared in 50-92% yield from CpTiCl3 and Bu-t(R)C=NLi. Analogous dimethyl compounds 1b-5b were prepare via methylation of dichlorides a using MeMgBr in 89-92% yield. Dimethyl compound 6b (L = C5Me5, R = CH(SiMe3)(2)) was prepared directly from Cp*TiMe3 and Bu-t[(Me3Si)(2)CH]C=NH in 40% yield. Dynamic H-1 NMR studies showed that the ketimide ligands in compounds b rotate rapidly about Ti-N on the NMR time scale, with a a Delta G(double dagger) of 9.6(6) kcal mol(-1) or less. The mixed alkyl compound Cp*-[Bu-t(R)C=N]Ti(CH3)CH2SiMe3 {R = (t)3u (7)} was prepared via alkylation of the corresponding methyl chloride derivative with BrMgCH2SiMe3. When treated with B(C6F5)(3), compounds 1b-6b are rapidly converted into the ion pairs {Cp[Bu-t(R)C=N]TiCH3}(+)[H3C(B(C6F5)(3)](-), 1c-6c; mixed alkyl compound 7 yields the ion pair [Cp*((Bu2C)-Bu-t=N)TiCH2SiMe3](+)[H3C(B(C6F5)(3)](-), 7c, exclusively. Multinuclear NMR experiments show that ion pairing is tight in these compounds and that ketimide ligand rotation is occurring with a slightly higher barrier in comparison to the neutral derivatives b. Ion pairs 1c-5e undergo a decomposition process involving loss of methane and producing the neutral compounds Cp[Bu-t(R)C=N]Ti(C6F5)[CH2B(C6F5)(2)], 1d-5d. The X-ray crystal structure of Id has been determined. Active cationic compounds are not regenerated from neutral compounds d in the presence of B(C6F5)(3) and thus this reaction is a potential deactivation pathway for these particular ion pairs. Detailed kinetic studies on the decomposition of 2c show the reaction to be first order in [2c] with activation parameters of Delta H-double dagger = 20.6(8) kcal mol(-1) and Delta S-double dagger = -8.5(10) eu, corresponding to Delta G(298)(double dagger) of 23.1(8) kcal mol(-1). A substantial kinetic isotope effect of k(H)/k(D) = 9.1(6) was measured using d(6)-2c. Further mechanistic experiments, including crossover and examination of alkane elimination from mixed alkyl ion pair 7c, point to a sigma-bond metathesis mechanism for the production of compounds d. The implications of our results for other, related catalyst systems are discussed.

  DOI：

  10.1021/ja994378c

文献信息

• The Mechanism of Methane Elimination in B(C₆F₅)₃-Initiated Monocyclopentadienyl-Ketimide Titanium and Related Olefin Polymerization Catalysts
  作者：Suobo Zhang、Warren E. Piers、Xiaoliang Gao、Masood Parvez

  DOI：10.1021/ja994378c

  日期：2000.6.1

  A new class of monocyclopentadienyl titanium olefin polymerization catalysts and their activation with B(C6F5)(3) is reported herein. Dichlorides Cp[Bu-t(R)C=N]TiCl2 Cp = C5H5, R = Bu-t (1a); Cp = C5Me5, R = Bu-t (2a); Cp = C5Me4SiMe3, R = Bu-t (3a); Cp = C5Me5, R = CH2SiMe3 (4a); Cp = C5Me5, R = Me (5a)} were prepared in 50-92% yield from CpTiCl3 and Bu-t(R)C=NLi. Analogous dimethyl compounds 1b-5b were prepare via methylation of dichlorides a using MeMgBr in 89-92% yield. Dimethyl compound 6b (L = C5Me5, R = CH(SiMe3)(2)) was prepared directly from Cp*TiMe3 and Bu-t[(Me3Si)(2)CH]C=NH in 40% yield. Dynamic H-1 NMR studies showed that the ketimide ligands in compounds b rotate rapidly about Ti-N on the NMR time scale, with a a Delta G(double dagger) of 9.6(6) kcal mol(-1) or less. The mixed alkyl compound Cp*-[Bu-t(R)C=N]Ti(CH3)CH2SiMe3 R = (t)3u (7)} was prepared via alkylation of the corresponding methyl chloride derivative with BrMgCH2SiMe3. When treated with B(C6F5)(3), compounds 1b-6b are rapidly converted into the ion pairs Cp[Bu-t(R)C=N]TiCH3}(+)[H3C(B(C6F5)(3)](-), 1c-6c; mixed alkyl compound 7 yields the ion pair [Cp*((Bu2C)-Bu-t=N)TiCH2SiMe3](+)[H3C(B(C6F5)(3)](-), 7c, exclusively. Multinuclear NMR experiments show that ion pairing is tight in these compounds and that ketimide ligand rotation is occurring with a slightly higher barrier in comparison to the neutral derivatives b. Ion pairs 1c-5e undergo a decomposition process involving loss of methane and producing the neutral compounds Cp[Bu-t(R)C=N]Ti(C6F5)[CH2B(C6F5)(2)], 1d-5d. The X-ray crystal structure of Id has been determined. Active cationic compounds are not regenerated from neutral compounds d in the presence of B(C6F5)(3) and thus this reaction is a potential deactivation pathway for these particular ion pairs. Detailed kinetic studies on the decomposition of 2c show the reaction to be first order in [2c] with activation parameters of Delta H-double dagger = 20.6(8) kcal mol(-1) and Delta S-double dagger = -8.5(10) eu, corresponding to Delta G(298)(double dagger) of 23.1(8) kcal mol(-1). A substantial kinetic isotope effect of k(H)/k(D) = 9.1(6) was measured using d(6)-2c. Further mechanistic experiments, including crossover and examination of alkane elimination from mixed alkyl ion pair 7c, point to a sigma-bond metathesis mechanism for the production of compounds d. The implications of our results for other, related catalyst systems are discussed.