application of chiralbisoxazoline (BOX) ligands in diverse metal-catalyzed asymmetricreactions results in growing demand for novel BOX ligands containing different motifs. Herein, the successful development of a chiral spiro bisoxazolineligand (TMSI-BOX) on the basis of the tetramethyl-1,1′-spirobiindane motif and bisoxazoline chelating units is described. The corresponding Fe complexes of TMSI-BOX
Toward a Large-Scale Approach to Milnacipran Analogues Using Diazo Compounds in Flow Chemistry
作者:Simon T. R. Müller、Aurélien Murat、Paul Hellier、Thomas Wirth
DOI:10.1021/acs.oprd.5b00308
日期:2016.2.19
The safe use of diazo reagents for the preparation of a key structure in the synthesis of milnacipran analogues is described herein. Using continuous flow technology, the diazo reagent is synthesized, purified, dried, and subsequently used in semi-batch mode for an intramolecular cyclopropanation. Side products formed in the reaction are isolated and rationalized to optimize the process. Different
An iron‐catalyzed asymmetric intramolecular cyclopropanation was realized in high yields and excellent enantioselectivity (up to 97 % ee) by using the iron complexes of chiral spiro‐bisoxazoline ligands as catalysts. The superiority of iron catalysts exhibited in this reaction demonstrated the potential abilities of this sustainable metal in asymmetric carbenoid transformation reactions.
Universal Strategy for the Immobilization of Chiral Dirhodium Catalysts
作者:Huw M. L. Davies、Abbas M. Walji
DOI:10.1021/ol0508835
日期:2005.7.1
[reaction: see text] Chiralrhodium(II) catalystsused in asymmetric carbenoid chemistry can be efficiently heterogenized using a novel immobilization strategy. The immobilized catalysts display similar reactivity and stereoselectivity to their homogeneous counterparts and can be effectively recycled with limited loss in stereoselectivity.