Practical Synthesis of Enantiomerically Pure β<sup>2</sup>-Amino Acids via Proline-Catalyzed Diastereoselective Aminomethylation of Aldehydes
作者:Yonggui Chi、Emily P. English、William C. Pomerantz、W. Seth Horne、Leo A. Joyce、Lane R. Alexander、William S. Fleming、Elizabeth A. Hopkins、Samuel H. Gellman
DOI:10.1021/ja070063i
日期:2007.5.1
efficiently transformed to protected beta2-amino acids, which are valuable building blocks for beta-peptides, natural products, and other interesting molecules. Because conditions for the aminomethylation and subsequent reactions are mild, beta2-amino acid derivatives with protected functional groups in the side chain, such as beta2-homoglutamic acid, beta2-homotyrosine, and beta2-homolysine, can be
脯氨酸催化的醛的非对映选择性氨甲基化使用手性亚胺离子,由易于制备的前体产生,提供 85:15 至 90:10 的 α-取代-β-氨基醛。α-取代-β-氨基醛可以还原为β-取代-γ-氨基醇,其主要的非对映异构体可以通过结晶或柱色谱分离。氨基醇被有效地转化为受保护的 β2-氨基酸,这是β-肽、天然产物和其他有趣分子的宝贵构建单元。由于氨甲基化和后续反应的条件温和,因此可以通过这种方法制备侧链具有保护官能团的β2-氨基酸衍生物,如β2-高谷氨酸、β2-高酪氨酸和β2-高赖氨酸。合成路线短,提纯简单;因此,该方法能够以有用的量制备受保护的β2-氨基酸。