或氨的diarylstannylene激活与的消除
Yang Peng1, Bobby D Ellis, Xinping Wang
1Department of Chemistry, University of California Davis, One Shields Avenue, Davis, California 95616, USA.
Journal of the American Chemical Society
|August 22, 2008
概括
重的斯坦尼SnAr'2很容易与H2,D2或NH3反应,形成新的化合物. 在相同的温和条件下,不太受硬质阻碍的斯坦尼保持不反应,突出显示了硬质散体对反应性的影响.
科学领域:
- 有机金属化学 有机金属化学
- 主群 化学 化学
- 和锡化学 和锡化学
背景情况:
- 斯坦尼烯是具有独特反应性的双价有机素化合物.
- 固体阻碍在低协调主组化合物的稳定性和反应中起着至关重要的作用.
研究的目的:
- 为了研究硬质要求高的斯坦尼烯与小分子的反应性.
- 了解固体体积对斯坦尼烯的反应通路的影响.
主要方法:
- 斯坦尼烯 (SnAr'2,SnAr2#,Sn{N(SiMe3) 2}2) 与H2,D2和NH3的反应3.
- 对反应产品和未发生反应的原材料进行分析.
- 反应性与电子性质的相关性 (n-p能量分离).
主要成果:
- 固态阻碍的斯坦尼SnAr'2与H2,D2和NH3发生反应,形成桥梁二次体:分别是{Ar'Sn(mu-H) }2,{Ar'Sn(mu-D) }2和{Ar'Sn(mu-NH2) }2.
- 较少拥挤的斯坦尼 (SnAr2#和Sn{N(SiMe3) 2}2) 在相同的条件下没有反应.
- 反应性的差异归因于n-p能量分离和单个二极根性质的变化.
结论:
- 固态阻碍对斯坦尼的反应性有显著影响,而重的替代物增强了对小分子的反应性.
- 在SnAr'2中较低的n-p能量分离与增加的单基二根性质和更大的反应性相关.
- 这项研究提供了关于有机化合物的结构-反应关系的见解.
相关概念视频
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Introduction
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
02:13Reduction of Alkenes: Catalytic Hydrogenation
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Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the surface of...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the surface of...
01:16Amines to Alkenes: Hofmann Elimination
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Under thermal conditions, the hydroxide can abstract a proton from the β carbon; this generates an alkene with the simultaneous...
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