Sun Alexander W, Hess Stephan N, Stoltz Brian M
Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering , Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , USA . Email:
Chem Sci. 2018 Oct 31;10(3):788-792. doi: 10.1039/c8sc03967d. eCollection 2019 Jan 21.
An enantioselective synthesis of diverse 4-Boc-protected α,α-disubstituted piperazin-2-ones using the palladium-catalyzed decarboxylative allylic alkylation reaction has been achieved. Using a chiral Pd-catalyst derived from an electron deficient PHOX ligand, chiral piperazinones are synthesized in high yields and enantioselectivity. The chiral piperazinone products can be deprotected and reduced to valuable -disubstituted piperazines. This reaction is further extended to enable the enantioselective synthesis of α,α-disubstituted tetrahydropyrimidin-2-ones, which are hydrolyzed into corresponding chiral β-amino acids.
通过钯催化的脱羧烯丙基烷基化反应实现了多种4-叔丁氧羰基保护的α,α-二取代哌嗪-2-酮的对映选择性合成。使用由缺电子PHOX配体衍生的手性钯催化剂，可高产率和对映选择性地合成手性哌嗪酮。手性哌嗪酮产物可脱保护并还原为有价值的α,α-二取代哌嗪。该反应进一步扩展，实现了α,α-二取代四氢嘧啶-2-酮的对映选择性合成，后者可水解为相应的手性β-氨基酸。
