Diastereo- and enantioselective intramolecular 1,6-C-H insertion reactions of alpha-diazo esters catalyzed by chiral dirhodium(II) carboxylates

作者：Ito Motoki; Kondo Yuji; Nambu Hisanori; Anada Masahiro; Takeda Koji; Hashimoto Shunichi^*

来源：Tetrahedron Letters, 2015, 56(11): 1397-1400.

DOI：10.1016/j.tetlet.2015.01.125

• Asymmetric catalysis
• Dirhodium(II) complex
• C-H insertion
• alpha-Diazo ester
• Six-membered heterocycle

The first catalytic asymmetric intramolecular 1,6-C-H insertion reaction of cc-diazo esters is described. With dirhodium(II) tetrakis[N-phthaloyl-(S)-tert-leucinate], Rh-2(S-VITL)(4), the C-H insertion proceeded in a chemoselective manner to give 2-alkenyltetrahydropyran-3-carboxylates with up to 95% ee and perfect cis diastereoselectivity.