1233532-48-3Relevant academic research and scientific papers
Asymmetric organocatalytic Michael addition of azlactones to cis-1,2-bis(phenylsulfonyl)ethene. A simple entry to quaternary α-amino acids
Bravo, Natalia,Alba, Andrea-Nekane R.,Valero, Guillem,Companyo, Xavier,Moyano, Albert,Rios, Ramon
, p. 1816 - 1820 (2010)
Azlactones react with 1,2-bis(phenylsulfonyl)ethene under catalysis by simple chiral thioureas, affording α,α-disubstituted α-amino acid derivatives in good yields and in moderate to good enantioselectivities.
Enantioselective organocatalytic addition of oxazolones to 1,1-bis(phenylsulfonyl)ethylene: A convenient asymmetric synthesis of quaternary α-amino acids
Alba, Andrea-Nekane R.,Companyo, Xavier,Valero, Guillem,Moyano, Albert,Rios, Ramon
scheme or table, p. 5354 - 5361 (2010/09/15)
A new, easy, and highly enantioselective method for the synthesis of quaternary α-alkyl-α-amino acids based on organocatalysis is reported. The addition of oxazolones to 1, 1-bis(phenylsulfonyl)ethylene is efficiently catalyzed by simple chiral bases or thioureas. The reaction affords α-disubstituted α-amino acid derivatives with complete C4 regioselectivity and with excellent yields and enantioselectivities. This methodology is complementary to previously reported enantioselec-tive approaches to quaternary ot-amino acids and allows the synthesis of αphenyl-α- alkyl-α-amino acids and αiert-butyl-α-alky1-α-amino acids. It has distinct advantages in terms of operational simplicity, enviromentally friendly conditions, and suitability for largescale reactions.
