使用顺磁性钴(II)卟啉催化剂[Co II (TPP)](TPP=四苯基卟啉)对邻烯丙基羰基-芳基N-芳基磺酰腙进行金属自由基活化,为合成新型8元杂环化合物提供了一种有效且强大的方法烯醇醚。该合成方案通用且实用,能够以高产率合成多种独特的 1 H -2-苯并氧辛。催化环化反应具有优异的化学选择性,具有较高的官能团耐受性,并为合成新的生物活性化合物提供了多种机会。该反应通过钴(III)-卡宾自由基中间体进行,该中间体参与从烯丙基位置到卡宾自由基的分子内氢转移(HAT),然后在钴的配位层中进行近无障碍的自由基反弹步骤。所提出的机制得到了实验观察、密度泛函理论(DFT)计算和自旋捕获实验的支持。
使用顺磁性钴(II)卟啉催化剂[Co II (TPP)](TPP=四苯基卟啉)对邻烯丙基羰基-芳基N-芳基磺酰腙进行金属自由基活化,为合成新型8元杂环化合物提供了一种有效且强大的方法烯醇醚。该合成方案通用且实用,能够以高产率合成多种独特的 1 H -2-苯并氧辛。催化环化反应具有优异的化学选择性,具有较高的官能团耐受性,并为合成新的生物活性化合物提供了多种机会。该反应通过钴(III)-卡宾自由基中间体进行,该中间体参与从烯丙基位置到卡宾自由基的分子内氢转移(HAT),然后在钴的配位层中进行近无障碍的自由基反弹步骤。所提出的机制得到了实验观察、密度泛函理论(DFT)计算和自旋捕获实验的支持。
sulfinamide bisphosphine catalysts (Wei‐Phos) were developed. These could be easily prepared from commercially available starting materials. Wei‐Phos has shown good performance in the very challenging intermolecular cross‐Rauhut–Currier reactions of vinyl ketones and 3‐acyl acrylates or 2‐ene‐1,4‐diones, leading to the R‐C products in high yields with up to 99 % ee under 2.5–5 mol% catalyst loading. The highly
The enantioselectiveintermolecular cross Rauhut-Currierreaction of acrolein with active olefins has been a long-standing challenge because of competitive MBH reaction and polymerization. Reported herein is a highly enantioselectiveintermolecular...
Organocatalytic Enantioselective Direct Vinylogous Michael Addition of α,β-Unsaturated γ-Butyrolactam to β-Acyl Acrylates and 1,2-Diacylethylenes
作者:Yi-Ru Chen、Utpal Das、Meng-Hsien Liu、Wenwei Lin
DOI:10.1021/jo5027047
日期:2015.2.6
A highly efficient Michaeladdition of α,β-unsaturated γ-butyrolactam to various β-acyl acrylates and ene-diones to provide synthetically useful compounds was developed. The products were obtained with high diastereo- and enantioselectivities (up to >25:1 dr and 99% ee) containing adjacent tertiary stereocenters.