Complementary chemistry! α‐Isocupreine (α‐ICPN) was synthesized for the first time in one step fromquinine by treatment with CF3SO3H (see scheme). This compound serves as an enantiocomplementarycatalyst to β‐isocupreidine (β‐ICD) in the Morita–Baylis–Hillman reaction.
互补化学!通过CF 3 SO 3 H处理,从奎宁一步一步合成了α-异cupreine(α-ICPN)(参见方案)。在Morita-Baylis-Hillman反应中,该化合物可作为β-异cupreidine(β-ICD)的对映体互补催化剂。
Invertible Enantioselectivity in 6′-Deoxy-6′-acylamino-β-isocupreidine-Catalyzed Asymmetric Aza-Morita−Baylis−Hillman Reaction: Key Role of Achiral Additive
作者:Nacim Abermil、Géraldine Masson、Jieping Zhu
DOI:10.1021/ol901920s
日期:2009.10.15
(1e)-catalyzed aza-Morita−Baylis−Hillmanreaction between N-sulfonylimines 3 and alkyl vinyl ketones 4 produced the (R)-enriched adducts 5. By adding a catalytic amount of β-naphthol (2a), the enantioselectivity of the same reaction was inversed leading to (S)-5 in excellent yields and enantioselectivities. Both aromatic and aliphaticimines are accepted as substrates for this reaction.
Mix and go: The quinidine amide 1 catalyzed [2+2] cycloaddition between N‐sulfonylimines 2 and alkyl 2,3‐butadienoates 3 afforded the R‐configured azetidines 4 in excellent yields and enantioselectivities (M.S.=molecular sieve). The S enantiomer was obtained when a quinine amide catalyst, the pseudoenantiomer of 1, was used.
Asymmetric organocatalytic decarboxylative Mannich reaction using β-keto acids: A new protocol for the synthesis of chiral β-amino ketones
作者:Chunhui Jiang、Fangrui Zhong、Yixin Lu
DOI:10.3762/bjoc.8.144
日期:——
The first decarboxylativeMannichreaction employing beta-keto acids, catalyzed by cinchonine-derived bifunctional thiourea catalyst has been described. The desired beta-amino ketones were obtained in excellent yields and with moderate to good enantioselectivities.