一價銠金屬催化α-酮酯進行具鏡像選擇性的烯丙基化反應：合成4’-芳基-2’,3’-二去氧核苷類似物

Abstract

本論文敘述利用一價銠金屬及掌性雙環[2.2.1]雙烯配基L8k配位形成之催化劑催化不同的烯丙基硼酸頻哪醇酯試劑14對α-酮酯7進行不對稱1,2-加成反應，以最優化條件進行反應，成功合成出一系列的掌性三級高烯丙醇2和71，產率高達>99%，鏡像超越值高達98%，非鏡像異構物比例高達>20:1。 此外，以加成產物2qa經5個步驟可得到掌性內酯ent-88，總產率為85%，再利用已知的方法能夠合成出具有抗HIV及抗癌活性的核苷類似物。

This thesis describes an asymmetric 1,2-addition of allyl boronic acid pinacol esters 14 to α-ketoesters 7, catalyzed by a chiral Rh(I)-catalyst, which in situ generated from [RhCl(C2H4)2]2 and the chiral bicyclo[2.2.1] heptadiene ligand L8k. Under optimal reaction conditions, the desired chiral tertiary homoallylic alcohols 2 and 71 were generated in up to >99% yield with up to 98% ee and up to >20:1 diastereomeric ratio. In addition, the homoallylic alcohol 2qa was converted, in 5 steps with 85% overall yields, to lactone ent-88 that is the crucial precursor for anti-HIV and anti-cancer nucleoside analogues.