Kelly Ann Rowley, Lurain Alice E, Walsh Patrick J
P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
J Am Chem Soc. 2005 Oct 26;127(42):14668-74. doi: 10.1021/ja051291k.
In this report, we outline a highly enantio- and diastereoselective one-pot method for the efficient synthesis of synthetically useful acyclic epoxy alcohols and allylic epoxy alcohols. Our method takes advantage of a highly enantioselective C-C bond-forming reaction to set the initial chirality. The resulting allylic zinc alkoxide intermediate is then epoxidized in situ using either dioxygen or TBHP in the presence of a titanium tetraalkoxide. Epoxy alcohols with up to three contiguous stereocenters are formed in one pot with excellent enantio- and diastereoselectivity. In cases where the zinc alkoxide intermediates contain two different allylic olefins, the more electron-rich double bond is chemoselectively epoxidized to afford an allylic epoxy alcohol. This method represents a highly efficient, stereoselective, and chemoselective approach to the synthesis of a wide range of useful epoxy alcohol and allylic epoxy alcohol products that were previously difficult to access.
在本报告中，我们概述了一种高效合成具有合成用途的无环环氧醇和烯丙基环氧醇的高度对映和非对映选择性一锅法。我们的方法利用高度对映选择性的碳 - 碳键形成反应来设定初始手性。然后，在四烷氧基钛存在下，使用氧气或叔丁基过氧化氢（TBHP）将所得的烯丙基锌醇盐中间体原位环氧化。具有多达三个相邻立体中心的环氧醇在一锅中以优异的对映和非对映选择性形成。在锌醇盐中间体含有两种不同烯丙基烯烃的情况下，电子密度更高的双键被化学选择性环氧化，得到烯丙基环氧醇。该方法代表了一种高效、立体选择性和化学选择性的方法，用于合成多种以前难以获得的有用环氧醇和烯丙基环氧醇产品。
