An enantiomerically pure sulfinyl group ortho to an aromatic amide imposes absolute stereochemistry on the conformation of its Ar-CO axis. Sulfoxide-lithium exchange followed by addition to an aldehyde relays the chirality of the amide axis to the new hydroxyl-bearing stereogenic centre with good stereochemical fidelity. Lactonisation of the hydroxyamide gives naphthofuranones and benzofuranones, including the fungal metabolite isoochracein, but with substrate-dependent stereoselectivity.
在芳香酰胺的邻位,若有一个对映纯的亚砜基团,则会对其Ar-CO轴的构型施加绝对的立体
化学控制。通过亚砜-
锂交换反应,随后与醛加成,可以将酰胺轴的手性传递给新的含羟基的手性中心,且立体
化学保真度良好。羟基酰胺的内酯化反应可以生成
萘并
呋喃酮和
苯并呋喃酮,包括真菌代谢物异赭色菌素,但底物依赖的立体选择性有所不同。