Fischer Theresa, Duong Qui-Nhi, García Mancheño Olga
Institute for Organic Chemistry, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany.
Straubing Center of Science for Renewable Resources, 94315, Straubing, Germany.
Chemistry. 2017 May 2;23(25):5983-5987. doi: 10.1002/chem.201605660. Epub 2017 Feb 16.
The first enantioselective synthesis of chiral heterocyclic α-amino phosphonates by nucleophilic dearomatization of quinolines and pyridines using an anion-binding organocatalysis approach is described. Chiral tetrakistriazoles were employed as efficient hydrogen-bond donor catalysts by forming a chiral close ion-pair with the in situ formed N-acyl salts and 2,2,2-trichlorethoxycarbonyl chloride (TrocCl). The ion-pair was subsequently treated with various phosphorus nucleophiles, such as silyl-protected dialkyl- and trialkylphosphites. Thus, the corresponding products were obtained in complete or high regioselectivities and up to 97:3 e.r. for quinolines or up to 89:11 e.r. for the more challenging pyridine substrates. This method allows for rapid access to substituted chiral cyclic α-amino phosphonates, which can be easily transformed into phosphonic acid derivatives.
描述了一种通过喹啉和吡啶的亲核去芳构化反应，利用阴离子结合有机催化方法首次对映选择性合成手性杂环α-氨基膦酸酯的方法。手性四唑用作高效的氢键供体催化剂，与原位形成的N-酰基盐和2,2,2-三氯乙氧基羰基氯（TrocCl）形成手性紧密离子对。随后用各种磷亲核试剂处理该离子对，例如硅基保护的二烷基和三烷基亚磷酸酯。因此，对于喹啉，以完全或高区域选择性获得相应产物，对映体比例高达97:3；对于更具挑战性的吡啶底物，对映体比例高达89:11。该方法能够快速获得取代的手性环状α-氨基膦酸酯，其可以很容易地转化为膦酸衍生物。
