Details

Autor(en) / Beteiligte

• Xu, Dan‐Qian
• Wang, Yi‐Feng
• Luo, Shu‐Ping
• Zhang, Shuai
• Zhong, Ai‐Guo
• Chen, Hui
• Xu, Zhen‐Yuan

Titel

A Novel Enantioselective Catalytic Tandem Oxa‐Michael–Henry Reaction: One‐Pot Organocatalytic Asymmetric Synthesis of 3‐Nitro‐2H‐chromenes

Ist Teil von

• Advanced synthesis & catalysis, 2008-11, Vol.350 (16), p.2610-2616

Ort / Verlag

Weinheim: WILEY‐VCH Verlag

Erscheinungsjahr

2008

Quelle

Wiley Online Library

Beschreibungen/Notizen

• An enantioselective oxa‐Michael–Henry reaction of substituted salicylaldehydes with nitroolefins that proceeds though an aromatic iminium activation (AIA) has been developed by using a chiral secondary amine organocatalyst and salicylic acid as a co‐catalyst. The corresponding 3‐nitro‐2H‐chromenes were obtained in moderate‐to‐good yields with up to 91% ee under mild conditions. Based on the experimental results and ESI‐mass spectrometric detection of the intermediates, a plausible transition state has been proposed to explain the origin of the activation and the asymmetric induction.