| Popis: |
A new chemical transformation for the construction of diversely functionalized cyclopropane-phosphorus derivatives utilizing chiron 4 and racemic diethyl α-hydroxylbenzylphosphonate as the key precursors is described. The diastereomeric pure phosphorus-containing derivatives 5a, 5′a, 5b and 5′b were obtained respectively, in good yields with d. e. 98% via asymmetric tandem double Michael addition/internal nucleophilic substitution of the corresponding compounds and further through the separation of the diastereomeric mixture by column chromatography. The diversely functionalized phosphorus derivatives are identified on the basis of their elemental analysis and spectroscopic data, such as K, 1H NMR, 13C NMR and MS. The absolute configuration of the interesting cyclopropane-phosphorus compound 5a was established by X-ray crystallography. Thus, these results provide a valuable strategy for synthesizing some biologically active molecules. |
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