Atroposelective attack of nucleophiles on 2-formyl-1-naphthamides and their derivatives: chelation and non-chelation control
作者:Jonathan Clayden、Catherine McCarthy、Neil Westlund、Christopher S. Frampton
DOI:10.1039/b000669f
日期:——
Organometallic nucleophiles attack 2-formyl-1-naphthamides to give secondary alcohols with widely varying atroposelectivity. By careful choice of reagent, selectivities of up to >99∶1 in favour of either the anti or the syn atropisomer can be obtained. Ethers and amines may be synthesised atroposelectively from acetals or imines. The sense of the selectivity is determined by the reactive conformation of the Ar–CHO bond, itself dependent on the coordinating and chelating ability of the nucleophile’s counterion. The roles of conformation, Lewis acids, and chelation/non-chelation control in relation to stereoselectivity are discussed.
有机金属核苷类物质攻击2-芳醛-1-萘酰胺,生成具有广泛变异的次级醇的非对映选择性。通过仔细选择试剂,可以获得高达99:1的选择性,偏向于反式或顺式对映异构体。醚类和胺类可以从缩醛或亚胺中选择性合成。选择性的方向由Ar–CHO键的反应构象决定,而这又依赖于核苷的配对离子的配位和螯合能力。文中讨论了构象、路易斯酸和螯合/非螯合控制与立体选择性之间的关系。