Catalytic Enantioselective Synthesis of the Phosphodiesterase Type IV Inhibitor (<i>R</i>)-(-)-Rolipram <i>via</i> Intramolecular C-H Insertion Process
作者:Masahiro Anada、Orie Mita、Hiroko Watanabe、Shinji Kitagaki、Shunichi Hashimoto
DOI:10.1055/s-1999-2958
日期:1999.11
A new route to the phosphodiesterase type IV inhibitor (R)-(-)-rolipram (1) has been developed, wherein the key step relies on enantioselective intramolecular C-H insertion of N-alkyl-N-4-nitrophenyl-α-methoxycarbonyl-α-diazoacetamide 7 catalyzed by chiral dirhodium(II) complex. The dirhodium(II) carboxylate, Rh2(S-BPTTL)4, incorporating N-benzene-fused-phthaloyl-(S)-tert-leucinate as a bridging ligand has proven to be the catalyst of choice for this process, providing the desired 2-pyrrolidinone 8 in 88% ee.
我们开发出了一种获得磷酸二酯酶 IV 型抑制剂 (R)-(-)-rolipram (1) 的新方法,其中的关键步骤是在手性二氢铑(II)络合物的催化下,将 N-烷基-N-4-硝基苯基-δ-甲氧羰基-δ-重氮乙酰胺 7 的 C-H 对映体选择性地插入分子内。事实证明,以 N-苯融合邻苯二甲酰-(S)-叔亮氨酸为桥接配体的羧酸二铑(II)Rh2(S-BPTTL)4 是这一过程的首选催化剂,它能以 88% 的ee 提供所需的 2-吡咯烷酮 8。