A number of salen-metal complexes were prepared and their enantioselective catalytic properties toward the asymmetric iodolactonization of （E）- and （Z）-5-substituted-4-pentenoic acid derivatives were investigated....A number of salen-metal complexes were prepared and their enantioselective catalytic properties toward the asymmetric iodolactonization of （E）- and （Z）-5-substituted-4-pentenoic acid derivatives were investigated. The catalyst system based on salen-Co（II） complex exhibited moderate to good enantioselectivity with the e.e. value ranging from 53% to 74%, as well as high regioselectivity of δ- vs. γ-iodolactones. The salen-Co（II） complex showed the highest enantioselectivity on the asymmetric iodolactonizations of （Z）-5-substituted-4-pentenoic acid derivatives among these reagent-controlled iodolactonization protocols known so far.展开更多
Skipped polyol is a common motif in numerous biologically significant polyketides and has been the focus of the development of novel synthetic methods and strategies. In this work, we devised a highly diastereoselecti...Skipped polyol is a common motif in numerous biologically significant polyketides and has been the focus of the development of novel synthetic methods and strategies. In this work, we devised a highly diastereoselective approach to access skipped triol(anti,syn-isomer) from a chiral α-allenic alcohol which was derived from kinetic resolution in our previous studies. An iodolactonization and subsequent radical deiodonation efficiently introduced the hydroxyl group at C3 in a highly diastereoselective manner and exemplified in enantioselective total synthesis of (+)-yashabushitriol.展开更多
文摘A number of salen-metal complexes were prepared and their enantioselective catalytic properties toward the asymmetric iodolactonization of （E）- and （Z）-5-substituted-4-pentenoic acid derivatives were investigated. The catalyst system based on salen-Co（II） complex exhibited moderate to good enantioselectivity with the e.e. value ranging from 53% to 74%, as well as high regioselectivity of δ- vs. γ-iodolactones. The salen-Co（II） complex showed the highest enantioselectivity on the asymmetric iodolactonizations of （Z）-5-substituted-4-pentenoic acid derivatives among these reagent-controlled iodolactonization protocols known so far.
基金This work was supported by the National Natural Science Foundation of China (21472186)the Shanghai Science and Technology Commission (15JC1400400)+1 种基金partially supported by the Ministry of Science and Technology (2011CB710800)Calvine Lai thanks the internship from ENSCL to conduct the summer research (June–August of 2013) in the Hong laboratory
文摘Skipped polyol is a common motif in numerous biologically significant polyketides and has been the focus of the development of novel synthetic methods and strategies. In this work, we devised a highly diastereoselective approach to access skipped triol(anti,syn-isomer) from a chiral α-allenic alcohol which was derived from kinetic resolution in our previous studies. An iodolactonization and subsequent radical deiodonation efficiently introduced the hydroxyl group at C3 in a highly diastereoselective manner and exemplified in enantioselective total synthesis of (+)-yashabushitriol.
