双语化学辞典Chem Lexicon
反应 · 有机化学 · 过渡金属催化 Organic chemistry · Transition-metal catalysis

烯烃复分解Olefin metathesis

拼音Pinyin xī tīng fù fēn jiě　别名Also 烯烃易位反应；复分解反应（烯烃）； alkene metathesis

定义Definition

烯烃复分解是在金属卡宾催化下，两个烯烃的 C=C 双键断裂并重新组合，交换亚烷基片段的反应。主要类型有交叉复分解、关环复分解、开环复分解聚合和非环二烯复分解聚合。

Olefin metathesis breaks and reforms C=C bonds of two alkenes under metal-carbene catalysis, swapping their alkylidene fragments. Main types: cross metathesis, ring-closing metathesis, ring-opening metathesis polymerisation and acyclic diene metathesis polymerisation.

肖万机理Chauvin mechanism

金属卡宾 M=CHR 与烯烃 [2+2] 环加成生成金属杂环丁烷，后者逆 [2+2] 断开另一组键，生成新的烯烃和新的金属卡宾，如此循环。反应可逆，常通过放出乙烯（关环复分解）或张力释放（开环聚合）驱动。

A metal carbene M=CHR and an alkene undergo [2+2] cycloaddition to a metallacyclobutane, whose retro-[2+2] along the other bonds gives a new alkene and carbene, continuing the cycle. Being reversible, it is driven by ethylene loss (RCM) or strain relief (ROMP).

催化剂Catalysts

早期为多相 Mo、W、Re 氧化物（工业上丙烯歧化、壳牌高级烯烃工艺）；施罗克的钼、钨亚烷基配合物活性极高但对空气、水敏感；格拉布斯的钌卡宾耐受官能团、易操作。

Early catalysts were heterogeneous Mo, W and Re oxides (propylene disproportionation, the Shell Higher Olefin Process); Schrock’s Mo/W alkylidenes are extremely active but air-sensitive; Grubbs’s ruthenium carbenes tolerate functional groups and are easy to handle.

意义Significance

肖万、格拉布斯、施罗克共获 2005 年诺贝尔化学奖。用于合成大环药物、天然产物、功能聚合物（如聚双环戊二烯）和石化产品（乙烯 + 2-丁烯 → 丙烯）。

Chauvin, Grubbs and Schrock shared the 2005 Nobel Prize. Applications include macrocyclic drugs, natural products, functional polymers (polydicyclopentadiene) and petrochemicals (ethylene + 2-butene → propylene).

反应Reactions

R1CH=CHR1 + R2CH=CHR2 ⇌ 2 R1CH=CHR2

格拉布斯或施罗克催化剂 1–5 mol%，CH₂Cl₂ 或甲苯，室温至 80 °C

1–5 mol % Grubbs or Schrock catalyst in CH₂Cl₂ or toluene, room temperature to 80 °C

  1. 金属卡宾与烯烃配位。

    Alkene coordinates to the metal carbene.

  2. [2+2] 生成金属杂环丁烷。

    [2+2] gives a metallacyclobutane.

  3. 逆 [2+2] 释放新烯烃和新卡宾。

    Retro-[2+2] releases a new alkene and carbene.

二烯丙基丙二酸二乙酯 Grubbs⟶ 环戊烯-1,1-二甲酸二乙酯 + CH2=CH2 Grubbs⟶ -1,1-Formic acid + CH2=CH2

关环复分解的标准底物。

The benchmark ring-closing metathesis.

年表Timeline

  • 1964

    班克斯与贝利报道丙烯歧化

    Banks and Bailey report propylene disproportionation

  • 1971

    肖万提出金属卡宾机理

    Chauvin proposes the metal-carbene mechanism

  • 1990

    施罗克钼催化剂

    Schrock’s molybdenum catalyst

  • 1995

    格拉布斯第一代催化剂

    Grubbs first-generation catalyst

  • 2005

    诺贝尔化学奖

    Nobel Prize in Chemistry