ChemInform Abstract: Stereoselective Synthesis of Chiral Pyrrolidine Derivatives of (+)‐α‐Pinene Containing a β‐Amino Acid Moiety.

Abstract

The (+)‐α‐pinene derived N‐protected amino acid (I) is used in the synthesis of several constrained pyrrolidine derivatives.

New Mesoporous Silica-Supported Organocatalysts Based on (2S)-(1,2,4-Triazol-3-yl)-Proline: Efficient, Reusable, and Heterogeneous Catalysts for the Asymmetric Aldol Reaction

“…Organocatalysts (2S,4R,1 S)-18 and (2S,4R,1 R)-18 incorporate an amide functional group in the (S)-proline-framework. This structural feature has proved rather successful in other organocatalysts derived from (S)-proline [42][43][44]. Furthermore, the fragment of (R)-or (S)-phenylethylamine was introduced to examine the potential effect of an additional center of chirality in the organocatalytic system.…”

“…In this context, several representative organocatalysts present two or more functional groups that act in cooperative or bifunctional strategies [12][13][14][15][16][17][18]. Several research groups have used natural and unnatural amino acids and peptides [19][20][21][22][23][24][25][26][27][28][29][30][31], chiral ureas and thioureas [32][33][34][35][36][37][38][39][40], and chiral amides [41][42][43][44][45] as building blocks or templates in organocatalyst design. In this context, a significant number of (S)-proline derivatives have been developed while searching for an improvement in the catalytic efficiency and stereoselectivity [46][47][48][49][50][51][52][53].…”