244104-74-3Relevant academic research and scientific papers
Sulfoxide-mediated diastereoselective Michael additions. New enantioselective synthesis of C-4 substituted 2-pyroaminoadipic acids
Acherki, Hassan,Alvarez-Ibarra, Carlos,Barrasa, Alicia,De Dios, Alfonso
, p. 5763 - 5766 (1999)
Diastereoselective reactions of suitably functionalized homochiral β-iminosulfoxides with Michael acceptors provide a new and efficient route for the asymmetric synthesis of C-4 substituted 2-pyroaminoadipates. Extension of the scope of the sulfoxide-mediated aza-enolate conjugate addition (Hua's reaction) has also been explored.
Total diastereoselectivity in the one-pot multistep reaction of (RS)-(+)-{[(4-methylphenyl)sulfinyl]methyl}-1-oxa-4-azaspiro[4.5]dec-3-ene and E-methyl cinnamate. An approach to (2S,4S,5R,6R)-2-(hydroxymethyl)-4,6-diphenyl-1-azabicycle[3.3.1]nonane
Alvarez-Ibarra, Carlos,Collados Lujan, Juan F.,Quiroga-Feijoo, Maria L.,Rodriguez, Gonzalo
, p. 1411 - 1413 (2008/12/21)
The base-mediated reaction of enantiomerically pure α-sulfinylketimine (+)-1 with (E)-methyl cinnamate afforded (+)-5a in a one-pot procedure with complete diastereoselectivity. A sole diastereomer of the eight possible ones was isolated which revealed the stereocontrol of the chiral sulfinyl group in the construction of the three new stereogenic centres. The absolute configuration of stereocentres introduced in (+)-5a was assigned on the basis of 1H NMR data and a single X-ray structure.
Diastereoselective synthesis of 4-substituted 5-(p-tolylsulfinyl)-5,6-dehydropiperidin-2-ones. A new approach to methyl L-(2S,4S)-4-methyl-6-oxopipecolate
Acherki, Hassan,Alvarez-Ibarra, Carlos,De Dios, Alfonso,Gutierrez, Marta,Quiroga, Maria L.
, p. 3173 - 3183 (2007/10/03)
The sulfoxide-mediated diastereoselective Michael reaction of homochiral α-sulfinylketimines 1a-d and β-substituted ene esters 2a-d (Hua's reaction) was explored. Straightforward cyclization of the open-chain adducts take place under the reaction conditions to provide the 4-substituted 5-(p-tolylsulfinyl)-5,6-dehydropiperidin-2-ones 3 and 7-12, whose stereochemistry is formed in the prior step. Furthermore, the role of the metal ion of the aza-enolate reagents and the steric demands of the O-alkyl ester group have been examined. It seems that the anti-diastereoselectivity depends on metal chelation by the oxygen of the ester as well as the oxygen of the sulfinyl group and the nitrogen in the aza-enolate ((Z)-configuration). In addition, the synthesis of methyl L-(2S,4S)-4-methyl-6-oxopipecolate has been achieved from the suitably functionalized 2-sulfinylketimine 1a (five steps; overall yield: 53-65%).
