Copper-catalyzed radical cascades of <i>para</i>-quinone methides with AIBN and H<sub>2</sub>O <i>via</i> α-cyanoalkylation by C–C bond cleavage: new access to benzofuran-2(3<i>H</i>)-ones
construction of a benzofuran-2(3H)-one scaffold via a radical cascade reaction of para-quinone methides with azodiisobutyronitrile and water. In the presence of CuI (20 mol%), this cascade proceeds smoothly through 1,6-conjugate addition/aromatization, α-cyanoalkylation by unstrained and non-polar C(aryl)–C(t-butyl) bondcleavage, and downstream cyano-insertion/cyclization/hydrolysis, which leads to
我们描述了第一单罐结构的苯并呋喃-2(3 H ^) -酮支架经由的自由基级联反应对用偶氮二异丁腈和水-quinone甲基化物。在存在CuI(20 mol%)的情况下,该级联过程通过1,6-共轭加成/芳构化,通过无应变和非极性的C(芳基)–C(叔丁基)键裂解以及下游的α-氰基烷基化而顺利进行氰基插入/环化/水解,可生成具有出色的官能团相容性的含氰基苯并呋喃-2(3 H)-酮。