鈷金屬錯合物催化一系列共軛烯類化合物1a-1g，可得到一系列β-碳對β-碳鍵結的還原偶合產物2a-2g，並具有高位向選擇，這樣的反應模式提供了非常直接、有效率的方法，在碳碳鍵的合成上，另外也提供了非常直接的方法去合成adipic acid。其次比較特殊的，若使用非共軛的烯類vinylarenes 3a-3l，則可得到雙偶合的產物4a-4l，而非還原偶合的產物，所得到的產物，也具有很好的位向選擇性，皆為E-form的形式。
另外，應用鈷金屬錯合物催化長鏈雙丙烯醯化合物5a-5i，可合成出一系列巨環環酯化合物6a-6i，也具有很好的位向及立體選擇性，並且只需再一般的濃度下0.25M，既可以有不錯的產率。其次，從實驗中也發現到一個效應，當長鏈雙丙烯醯化合物的長鏈中，具有異核原子時，會使異核原子配位到鈷金屬上，造成自身偶合反應速率大於分子間偶合反應。
另一方面，發現到鈷金屬錯合物也可以催化炔類與共軛烯類形成一系列還原偶合產物8a-8j，並具有很好的位向及立體選擇性。更可催化炔烯類化合物進行還原偶合反應，可得到14環的巨環雙酯化合物12a-12c，都有不錯的反應結果。
嘗試使用炔類上具有-OH取代基的propargyl alcohol與methyl acrylate 1d，在鈷金屬錯合物的催化下，進行還原偶合反應，確實可以得到預期的產物，六環環酯化合物 (δ-lactones) 9a-9h。所得到的環酯化合物是一系列的γ-methylideneδ-lactones，在γ位置有一個烯類的取代基。其次把炔類上改使用具有-NH取代基的propargyl amine與methyl acrylate 1d，在鈷金屬錯合物的催化下，進行還原偶合反應，確實也可得到預期的產物，六環環醯化合物 (δ-lactame) 9i-9k。
設計合成出炔類的二端取代基，分別具有methoxycarbonyl和HO-基的反應物，與共軛烯類進行反應，在鈷金屬錯合物催化下，發現可以形成一系列七環環酯化合物10a-10i，並具有很好的位向及立體選擇性。這樣的反應模式，在以往文獻中，並未被報導。
對於反應機構，到現在還不是很了解，我們做了一些簡單的實驗，將有助於反應機構的推測。

In this work, we report two cobalt-catalyzed olefins dimerization modes: (a) reductive dimerization of conjugated alkenes to yield directly the saturated linear diesters, dinitrile, and disulfone 2a-2g, offering a more convenient method to the synthesis of adipic acid and, (b) cobalt-catalyzed head-to-tail dimerization of vinylarenes 4a-4l in good yields.
On the other hand, we have recently developed a reaction mode of cobalt-catalyzed tail-to-tail reductive dimerization of conjugated alkenes. This provides an efficient and mild route for the corresponding saturated linear products. Herein, we describe that application for the cobalt-catalyzed reaction mode to synthesis of macrocyclic di- and tetralactones 6a-6i in good yields under normal dilution conditions.
The cobalt-catalyzed highly regio- and stereoselective reductive coupling reaction of alkynes and conjugated alkenes to form a new chain molecule 8a-8j, was conducted in the presence of CoI2(L) and zinc metal powder. Several 4-(4-alkyl phenyl)-3-butynyl acrylates also undergo reductive coupling macrocyclicization reaction to afford macrocyclic dilactone 12a-12c in 45-80% yields. This procedure allows for the synthesis of a variety of functionalized lactones, lactames and macrocyclic dilactones in moderate to good yields. Treatment of various propargyl alcohol with methyl acrylate proceeded successfully in the presence of CoI2(dppe), water and zinc metal powder in a mixture of acetonitrile and 1,4-dioxane (v/v = 1/1) at 80℃ affording the corresponding γ-methylideneδ-lactones 9a-9h in good yields. Several propargyl amines also react with methyl acrylate to afford γ-methylideneδ-lactames 9i-9k in 72-84% yields. Seven-membered lactones 10a-10i could also be prepared by slow addition of methyl 2-(3-hydroxy-1-alkynyl)benzoate to the reaction mixture of conjugated alkene in presence of CoI2(dppe), water and zinc metal powder and acetonitrile at 80℃. The above catalytic reactions are completely regioselective and highly stereoselective. Possible mechanisms for the reductive coupling cyclization reactions as well as unique features of these processes are discussed.

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