81039-06-7Relevant academic research and scientific papers
Asymmetric Domino Reaction of α,β-Unsaturated Aldehydes and α-Acyl α,β-Unsaturated Cyclic Ketones Catalyzed by Diphenylprolinol Silyl Ether
Hayashi, Yujiro,Suga, Yurina,Umekubo, Nariyoshi
supporting information, (2020/11/18)
An asymmetric domino reaction combining vinylogous Michael reaction, hydration of aldehyde, and oxy-Michael reaction proceeds with α,β-unsaturated aldehydes and α-acyl α,β-unsaturated cyclic ketones in the presence of diphenylprolinol silyl ether to afford tetrahydrochromane derivatives with excellent enantioselectivity. After the domino reaction, addition of Wittig reagent and acid in the same reaction vessel promoted a second domino reaction incorporating retro oxy-Michael reaction, isomerization, and Wittig reaction to afford chiral functionalized cyclic 1,3-diene derivatives with excellent enantioselectivity. Overall, six reaction steps proceed in a one-pot procedure.
Asymmetric conjugate additions to 1,1′-diactivated cyclic enones-a comparative study
Tang, Xiaoping,Blake, Alexander J.,Lewis, William,Woodward, Simon
experimental part, p. 1881 - 1891 (2010/02/27)
A study of copper-phosphoramidite-catalysed ZnR2 and AlR3 additions to 1,1′-dicarbonyl-activated cyclic Michael acceptors has revealed high enantioselectivities for AlR3 (R = Me, Et) 1,4-addition to a range of 3-acylcoumarins (85-98% ee, trans:cis ~90:10) using commercial or readily available ligands. Large substituents at the 6-position, and to some extent at the 5-position, of the coumarin are less well tolerated, nor is truncation of the coumarin motif to a comparable 2-acylcyclohexenone (ee values up to 78%).
