1602489-93-9Relevant academic research and scientific papers
Catalytic, asymmetric synthesis of phosphonic γ-(hydroxyalkyl) butenolides with contiguous quaternary and tertiary stereogenic centers
Frings, Marcus,Thome, Isabelle,Schiffers, Ingo,Pan, Fangfang,Bolm, Carsten
supporting information, p. 1691 - 1700 (2014/03/21)
A procedure that enables high yielding access to phosphonic γ-(hydroxyalkyl)butenolides with excellent regio-, diastereo- and enantiocontrol is reported. The simultaneous construction of up to two adjacent quaternary stereogenic centers by a catalytic asymmetric vinylogous Mukaiyama aldol reaction unites biologically and medicinally relevant entities, namely α-hydroxy phosphonates and γ-(hydroxyalkyl)butenolides. This is achieved by utilizing a readily available chiral copper-sulfoximine catalyst showing a broad functional group tolerance for both the electrophilic and nucleophilic reactants. A discussion about potential factors affecting the observed level of enantioselectivity, which stems from the enantiopure sulfoximine ligand, is also included. Best of two worlds: A chiral copper-sulfoximine catalyst unites biologically relevant α-hydroxy phosphonates and γ-(hydroxyalkyl) butenolides into one structural motif with regio-, diastereo- and enantioselectivity up to the limits of detection (see scheme; Tf=trifluoromethanesulfonyl, TMS=trimethylsilyl). Copyright
