Whitehead Alan, McParland James P, Hanson Paul R
Department of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045-7582, USA.
Org Lett. 2006 Oct 26;8(22):5025-8. doi: 10.1021/ol061756r.
Desymmetrization of a readily derived pseudo-C(2)-symmetric monocyclic phosphate via highly diastereoselective anti-S(N)2' allylic displacement reactions is reported. This method utilizes of a wide variety of zinc-derived organocuprates to afford E-1,2-syn-configured phosphate acid building blocks. Extension of this protocol to unsymmetric monocyclic phosphates exclusively yields 1,2-anti-configured products. Within this study, stereoelectronic factors, coupled with allylic strain, ultimately govern regio- and diastereoselective cuprate reactions, further substantiating the Corey mechanism for organocuprate additions into allylic esters. [reaction: see text]
报道了通过高度非对映选择性反-S(N)2'烯丙基取代反应，对一种易于衍生的拟C(2)对称单环磷酸酯进行去对称化。该方法利用多种锌衍生的有机铜酸盐，得到E-1,2-顺式构型的磷酸酸构建块。将该方案扩展到不对称单环磷酸酯时，只生成1,2-反式构型的产物。在本研究中，立体电子因素与烯丙基张力共同最终控制区域和非对映选择性铜酸盐反应，进一步证实了有机铜酸盐加成到烯丙基酯中的科里机理。[反应：见正文]
