开发了铑催化的邻位选择性卡宾插入策略以激活β-咔啉和异喹啉支架的非酸性 sp 2 C H 键。这种转变利用吡啶氮的导向特性,使 C C 键的制造具有高原子经济性、良好的产率和广泛的官能团耐受性。在该协议中,丙二酸二乙酯、二甲基二甲酮和羟吲哚的重氮化合物作为卡宾源进行了测试,释放了对环境无害的 N 2气体作为副产品。此外,为了了解机理,进行了 ESI-MS 研究,并确定了与这种转变相关的关键中间体。此外,由合成的产物完成了平面多环中氮茚-吲哚骨架的无金属结构。此外,还确定了 C N 环状化合物的肿瘤和荧光特性。
开发了一种通过Cu( II ) 催化氧化 1,2,3,4-四氢-β-咔啉 (THβCs)合成芳香族 β-咔啉的温和、高效和环保的方法,其中空气 (O 2 )用作清洁氧化剂。该方法具有环境友好、温和、官能团耐受性好、收率高、实验操作简单等优点。此外,该新方法成功应用于高效实用的β-咔啉生物碱perlolyrine和flalazin的全合成。
PhI(OAc)<sub>2</sub>-mediated one-pot oxidative decarboxylation and aromatization of tetrahydro-β-carbolines: synthesis of norharmane, harmane, eudistomin U and eudistomin I
A new strategy for synthesis of β-carbolines via one-pot oxidative decarboxylation at room temperature is developed for the first time.
首次开发了一种在室温下通过一锅法氧化脱羧合成β-咔啉的新策略。
Reusable, homogeneous water soluble photoredox catalyzed oxidative dehydrogenation of N-heterocycles in a biphasic system: application to the synthesis of biologically active natural products
the substrate and catalyst at room temperature. Its potential applications to organic transformations are demonstrated by the synthesis of various biologically active N-heterocycles such as indoles, (iso)quinolines and β-carbolines and natural products such as eudistominU, norharmane, and harmane and precursors to perlolyrine and flazin. Without isolation and purification, the catalyst solution can
Employing TBN/TEMPO as the catalysts and oxygen as the oxidant, the biologically and pharmaceutically significant tetrahydro-β-carboline and β-carboline alkaloid scaffolds that used to be obtained by multi-step processes can now be selectively obtained in only one-step via direct aerobicoxidative Pictet–Spengler reactions of tryptamines with alcoholsundermildconditions, with water generated as
DBN has been identified as an efficient reagent for promoting the dehydrogenative/decarboxylative aromatization of tetrahydro-β-carbolines under air atmosphere, to access the corresponding β-carbolines in moderate to good yields. The utility of this protocol for the gram-scale synthesis of β-carboline alkaloids eudistomin U (7) and harmane (10) has also been demonstrated.
A convenient and efficient metal free, atom economical flexible synthesis of β-carbolines involving a domino Pictet-Spengler reaction and aromatization in oxygen atmosphere in N-methyl-2-pyrollidone (NMP) is described. Variety of aryl, heteroaryl and aliphatic aldehydes were found to be good substrates for this methodology. Several β-carbolines (6a-6t) and β-carboline methylesters (7a-7e) were synthesized