The organocatalyzed regioselective allylic trifluoromethylation of Morita–Baylis–Hillman adducts using Ruppert–Prakash reagent was achieved in high to excellent yields via a successive SN2′/SN2′ mode for the first time. The reaction was extended to the asymmetric allylic trifluoromethylation by the use of a bis-cinchona alkaloid catalyst with high enantioselectivities up to 94% ee.
首次通过连续的S N 2'/ S N 2'模式,使用Ruppert-Prakash试剂对Morita-Baylis-Hillman加合物进行了有机催化的区域选择性烯丙基三氟甲基化反应,收率很高。通过使用具有高达94%ee的高对映选择性的双金鸡纳生物碱催化剂,反应扩展到不对称的烯丙基三氟甲基化反应。
Asymmetric [3+2] Cycloaddition of Olefins with Morita–Baylis–Hillman Carbonates Catalyzed by BINOL-Based Bifunctional Phosphine
作者:Hai-Lei Cui、Xue Tang、Meng-Fan Li、Xing-Jie Xu、Yin Shi
DOI:10.1055/s-0037-1611752
日期:2019.4
series of novel BINOL-based phosphines. These bifunctional organocatalysts can be used in the [3+2] cycloaddition of electron-deficient olefins and Morita–Baylis–Hillman (MBH) carbonates. Moderate to excellent yields (up to >99%) and good to excellent enantioselectivities (up to 95% ee) can be obtained in the cycloaddition reaction of maleimides and MBH carbonates. The application of these novel phosphines
Highly Enantioselective [3+2] Annulation of Morita-Baylis-Hillman Adducts Mediated by L-Threonine-Derived Phosphines: Synthesis of 3-Spirocyclopentene-2-oxindoles having Two Contiguous Quaternary Centers
作者:Fangrui Zhong、Xiaoyu Han、Youqing Wang、Yixin Lu
DOI:10.1002/anie.201102094
日期:2011.8.16
Spiral bound: The Morita–Baylis–Hillmanadducts were employed as C3 synthons in the asymmetric [3+2] annulation with malonitrile substrates using L‐threonine‐derived 1 as the catalyst (see scheme). The reaction is highly regioselective and stereoselective, and affords optically enriched 3‐spirocyclopentene‐2‐oxindoles containing twocontiguousquaternarycenters. Boc=tert‐butoxycarbonyl, PMB=para‐methoxybenzyl
Pd(II)/β-ICD-Cocatalyzed Asymmetric Route to Oxindole Scaffold via Cascade Reaction of Diazoacetamides and MBH-Carbonates
作者:Yang Yang、Chaoqun Ma、Nilesh J. Thumar、Wenhao Hu
DOI:10.1021/acs.joc.6b01703
日期:2016.9.16
report an efficient method for asymmetricsynthesis of chiral oxindoles. Allyl palladium(II) chloride dimer (APC)-catalyzed, in combination with β-isocupreidine (β-ICD)-cocatalyzed, reaction of diazoacetamide with Morita–Baylis–Hillman (MBH) carbonates proves to be a facile protocol to access multifunctional oxindoles bearing a C-3 quaternary stereo center. This tandem reaction tolerates a wide variety of