A new and flexible route for the asymmetricsynthesis of a variety of alkylated bridged tetrahydro-2-benzazepines has been developed. The key steps are the highly diastereoselective Michael addition of metalated SAMP-hydrazones to α,β-unsaturated esters combined with cyclomethylenation/Mitsunobu coupling reactions to secure the formation of the seven-membered azaheterocycle and of the bridged unit
A convenient method for the synthesis of 3,4-disubstituted-2,3,4,5-tetrahydro-2-benz-azepines in high diastereoselective excess has been elaborated. The key steps are the highly stereoselective metallation/alkylation and nucleophilic 1,2-addition reaction on SAMP-hydrazones. Cyclomethylenation followed by N-N bond cleavage completes the synthesis of the titled compounds.
已详细阐述了一种合成 3,4-二取代-2,3,4,5-四氢-2-苯并氮杂高非对映选择性过量的简便方法。关键步骤是 SAMP-腙的高度立体选择性金属化/烷基化和亲核 1,2-加成反应。环亚甲基化和 NN 键断裂完成标题化合物的合成。
Total synthesis of ionophore antibiotic X-14547A
作者:K. C. Nicolaou、D. P. Papahatjis、D. A. Claremon、R. L. Magolda、R. E. Dolle
DOI:10.1021/jo00209a017
日期:1985.5
Total synthesis of ionophore antibiotic X-14547A. 1. Enantioselective synthesis of the tetrahydropyran and tetrahydroindan building blocks
作者:K. C. Nicolaou、D. P. Papahatjis、D. A. Claremon、R. E. Dolle