Enantio- and diastereoselective synthesis of cis-2-aryl-3-methoxycarbonyl-2,3-dihydrobenzofurans via the Rh(II)-catalyzed C-H insertion process.
[formula: see text] The enantioselective intramolecular C-H insertion reaction of aryldiazoacetates has been explored with use of dirhodium(II) carboxylate catalysts, which incorporate N-phthaloyl- or N-benzene-fused-phthaloyl-(S)-amino acids as chiral bridging ligands. Dirhodium tetrakis[N-phthaloyl-(S)-tert-leucinate], Rh2(S-PTTL)4, has proven to be the catalyst of choice for this process, providing exclusively cis-2-aryl-3-methoxycarbonyl-2,3-dihydobenzofurans in up to 94% ee.
Saito
Hiroaki
H
Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
Oishi
Hiroyuki
H
Kitagaki
Shinji
S
Nakamura
Seiichi
S
Anada
Masahiro
M
Hashimoto
Shunichi
S