A series of bifunctional primary amine-thiophosphoramides were synthesized, which proven to be effective organocatalysts for the asymmetric Michael reaction of acetone to both aryl and alkyl nitro olefins in the presence of phenol as a protic additive. The corresponding adducts were obtained in excellent chemical yields (up to >99 %) with excellent enantioselectivities (up to 97 % ee).
1,2‐Diamine‐Derived (thio)Phosphoramide Organocatalysts in Asymmetric Michael Additions
作者:Viktória Kozma、Ferenc Fülöp、György Szőllősi
DOI:10.1002/adsc.202000335
日期:2020.6.15
Phosphoramides and thiophosphoramides were prepared from optically pure C2‐symmetric 1,2‐diamines and were used as chiral organocatalysts in the asymmetric Michael additions of aldehydes and ketones to N ‐substituted maleimides. The 1,2‐diphenylethane‐1,2‐diamine derived thiophosphoramide, which could be prepared in good yield in a one‐step procedure, was found to be more active and selective catalyst