Synthesis of an Enantiocomplementary Catalyst of β-Isocupreidine (β-ICD) from Quinine
作者:Ayako Nakano、Mina Ushiyama、Yoshiharu Iwabuchi、Susumi Hatakeyama
DOI:10.1002/adsc.200505138
日期:2005.11
Compound 20, a pseudoenantiomer of β-isocupreidine (β-ICD), was synthesized from quinine employing a Barton reaction of nitrosyl ester 13 and acid-catalyzed cyclization of carbinol 18 as key steps. The Baylis–Hillman reaction of benzaldehyde, p-nitrobenzaldehyde, and hydrocinnamaldehyde with 1,1,1,3,3,3-hexafluoroisopropyl acrylate (HFIPA) using 20 as a chiral amine catalyst was found to give the corresponding
使用亚硝酰基酯13的Barton反应和甲醇18的酸催化环化反应,由奎宁合成了化合物20,一种β-异cupreidine(β-ICD)的假对映体。使用20作为手性胺催化剂,发现苯甲醛,对硝基苯甲醛和氢肉桂醛与1,1,1,3,3,3-六氟异丙基丙烯酸酯(HFIPA)的Baylis-Hillman反应产生了相应的S-加合物。与β-ICD催化的反应可提供富R的加合物相比,具有较高的光学纯度(> 91%ee)。该结果表明化合物20 可以在醛类与HFIPA的不对称Baylis-Hillman反应中作为β-ICD的对映体互补催化剂。