A family of novel bifunctional organocatalysts: Highly enantioselective alcoholysis of meso cyclic anhydrides and its application for synthesis of the key intermediate of P2X7 receptor antagonists
Abstract A family of novel squaramides/sulfamides based on 1,2-alkamine was developed as chiral bifunctional catalysts to promote the asymmetric alcoholysis of meso cyclic anhydrides. The hemiesters were obtained in high yield with up to 93% ee. The usefulness of this methodology was demonstrated in the asymmetric synthesis of the key intermediate of P2X7 receptor antagonists.
Development of Bifunctional Thiourea Organocatalysts Derived from a Chloramphenicol Base Scaffold and their Use in the Enantioselective Alcoholysis of<i>meso</i>Cyclic Anhydrides
chloramphenicol‐base‐derived thiourea organocatalysts, (1S,2R)‐12 a–f and (1R,2R)‐15 a–c, and their use in the enantioselectivealcoholysis of meso‐anhydrides are described. In particular, hemiesters afforded excellent enantioselectivities if low loadings of (1S,2R)‐12 a–f were used. Almost no enantioselectivities were achieved with the use of (1R,2R)‐15 a–c. This technique was used to synthesize (R)‐(−)‐baclofen
新的氯霉素基硫脲有机催化剂(1 S,2 R)-12 a - f和(1 R,2 R)15 a - c的合成及其在介孔酸酐的对映选择性醇解中的应用描述。特别是,如果使用低负荷的(1 S,2 R)-12 a – f负载,半酯具有出色的对映选择性。使用(1 R,2 R)‐ 15 a – c几乎没有达到对映选择性。该技术用于合成(R)-(-)-baclofen。