一價銠金屬催化苯並環丁醇具位向選擇之開環反應及其接續與馬來醯亞胺之共軛加成反應
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2016
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本篇論文探討利用Rh(I)銠金屬催化劑催化苯並環丁醇36進行選擇性斷C(sp2)‐C(sp3)鍵隨後再和馬來醯亞胺51進行反應。在0.015莫耳的銠金屬[Rh(cod)(OH)]2催化劑催化苯並環丁醇36進行位置選擇性開環，中間體芳基銠金屬化合物再和馬來醯亞胺進行共軛加成反應最後和酮基進行醛醇反應。生成主要產物化合物52具有六員環與五員環順式相駢的結構，且羥基的位向與橋頭氫原子為順式的關係;反之另一次要非鏡像異構物53，羥基與橋頭氫原子則為反式關係。另有單離得到次要化合物54，則為單進行共軛加成反應，沒有進行醛醇反應的產物。
This thesis describes the employment of [Rh(cod)(OH)]2 as a catalyst in the site-selective cleavage of C(sp2)‐C(sp3) the bond of benzocyclobutenols 36 and their subsequent reaction with maleimides 51. In the presence of 1.5 mol% of [Rh(cod)(OH)]2, ring-opening reaction of benzocyclobutenols 36 proceed in a regioselective manner, allowing a two-step reaction involving a conjugation addition reaction of the thus-obtained Ar-Rh species with maleimides 45 and an aldol reacton with the resulting ketone group. The major products 52 consist of cis-fused 6-membered and 5-membered rings with the stereochemistry of hydroxyl group cis to the bridged head H-atoms, whereas the hydroxyl group is trans to bridged head H-atoms in the minor diastereomers 53. The intermediate 54, resulting from the initial conjugated addition of Ar-Rh to 45, was isolated as the minor product.
This thesis describes the employment of [Rh(cod)(OH)]2 as a catalyst in the site-selective cleavage of C(sp2)‐C(sp3) the bond of benzocyclobutenols 36 and their subsequent reaction with maleimides 51. In the presence of 1.5 mol% of [Rh(cod)(OH)]2, ring-opening reaction of benzocyclobutenols 36 proceed in a regioselective manner, allowing a two-step reaction involving a conjugation addition reaction of the thus-obtained Ar-Rh species with maleimides 45 and an aldol reacton with the resulting ketone group. The major products 52 consist of cis-fused 6-membered and 5-membered rings with the stereochemistry of hydroxyl group cis to the bridged head H-atoms, whereas the hydroxyl group is trans to bridged head H-atoms in the minor diastereomers 53. The intermediate 54, resulting from the initial conjugated addition of Ar-Rh to 45, was isolated as the minor product.
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銠金屬催化, 苯並環丁醇, 共軛加成, 馬來醯亞胺, rhodium(I)-catalysted, benzocyclobutenol, conjugate Addition, maleimide