22671-33-6Relevant academic research and scientific papers
Bifunctional Br?nsted Base Catalyst Enables Regio-, Diastereo-, and Enantioselective Cα-Alkylation of β-Tetralones and Related Aromatic-Ring-Fused Cycloalkanones
Urruzuno, I?aki,Mugica, Odei,Oiarbide, Mikel,Palomo, Claudio
, p. 2059 - 2063 (2017)
The catalytic asymmetric synthesis of both α-substituted and α,α-disubstituted (quaternary) β-tetralones through direct α-functionalization of the corresponding β-tetralone precursor remains elusive. A designed Br?nsted base-squaramide bifunctional catalyst promotes the conjugate addition of either unsubstituted or α-monosubstituted β-tetralones to nitroalkenes. Under these reaction conditions, not only enolization, and thus functionalization, occurs at the α-carbon atom of the β-tetralone exclusively, but adducts including all-carbon quaternary centers are also formed in highly diastereo- and enantioselective manner.
β2, 2-Amino Acid N-Carboxyanhydrides Relying on Sequential Enantioselective C(4)-Functionalization of Pyrrolidin-2,3-diones and Regioselective Baeyer–Villiger Oxidation
Badiola, Eider,Olaizola, Iurre,Vázquez, Ana,Vera, Silvia,Mielgo, Antonia,Palomo, Claudio
supporting information, p. 8185 - 8195 (2017/06/23)
A catalytic enantioselective entry to β2, 2-amino acids enabling their direct coupling with nucleophiles is described. The approach is based upon an effective bifunctional Br?nsted base catalyzed construction of a quaternary carbon stereocenter at C4 position of pyrrolidin-2,3-diones. Subsequent regioselective Baeyer–Villiger oxidation of the resultant adducts gives β2, 2-amino acid N-carboxyanhydrides as the reactive species, which can further react with nucleophiles. Following this strategy both, β2, 2-amino acid derivatives with different functionalities at the newly created stereocenter, and spirocyclic structures can be efficiently prepared.
