State Key Laboratory of Applied Organic Chemistry & School of Pharmacy, Lanzhou University, Lanzhou 730000, P. R. China.
Chem Commun (Camb). 2019 Mar 26;55(26):3789-3792. doi: 10.1039/c9cc00811j.
A facile and efficient method to form a chiral multi-substituted 3H-spiro[benzofuran-2,1'-cyclopentane] structural unit has been developed via a one-pot [3+2] cyclization/semipinacol rearrangement cascade. A catalysis system of Cu(ii)/BOX has been used to efficiently construct a key stereogenic center via a cyclization between substituted benzoquinones and allylic alcohols affording the desired products in good yields and with excellent enantioselectivities and diastereoselectivities (21 examples; up to 67% yields; up to 92% ee and up to >20 : 1 dr). This method provides an alternative strategy for the synthesis of the corresponding bioactive molecules containing spiro[benzofurancyclopentane] skeleton units.
一种通过一锅[3+2]环化/半频哪醇重排级联反应形成手性多取代 3H-螺[苯并呋喃-2,1'-环戊烷]结构单元的简便高效方法已经被开发出来。使用 Cu(ii)/BOX 催化体系通过取代的苯醌和烯丙醇之间的环化反应有效地构建了关键的立体中心，以良好的收率、优异的对映选择性和非对映选择性（21 个实例；高达 67%的产率；高达 92%的ee 值和高达>20：1 的 dr）得到了所需的产物。该方法为含有螺[苯并呋喃环戊烷]骨架单元的相应生物活性分子的合成提供了一种替代策略。
