Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany.
Org Lett. 2012 Aug 17;14(16):4254-7. doi: 10.1021/ol301983f. Epub 2012 Aug 1.
An efficient one pot asymmetric synthesis of tetrahydropyrano[2,3-c]pyrazoles has been developed. This class of biologically active heterocycles can be obtained via a secondary amine catalyzed asymmetric Michael/Wittig/oxa-Michael reaction sequence. Remarkably, the title compounds were accessible in good to very good yields and very good to excellent enantioselectivities after a single purification step.
已开发出一种高效的一锅不对称合成四氢吡喃并[2,3-c]吡唑的方法。通过二级胺催化的不对称迈克尔加成/Wittig/氧杂-Michael 反应序列,可以获得这类具有生物活性的杂环化合物。值得注意的是,在经过单一纯化步骤后,标题化合物可以以良好到非常好的收率和非常好到优秀的对映选择性获得。