Iodine-catalyzed chemoselective dehydrogenation and aromatization of tetrahydro-β-carbolines: A short synthesis of Kumujian-C, Eudistomin-U, Norharmane, Harmane Harmalan and Isoeudistomine-M
作者:Sunil Gaikwad、Dayanand Kamble、Pradeep Lokhande
DOI:10.1016/j.tetlet.2018.04.043
日期:2018.6
Temperature controlled chemoselective dehydrogenation and aromatization of tetrahydro-β-carbolines, using molecular I2 and H2O2, in DMSO solvent affords a practical access to a series of corresponding 3,4-dihydro-β-carbolines and β-carbolines respectively. This method has been successfully employed in the short synthesis of Kumujian-C, Eudistomin-U, Norharmane Harmane Harmalan and Isoeudistomin-M.
在DMSO溶剂中使用分子I 2和H 2 O 2对四氢-β-咔啉进行温度控制的化学选择性脱氢和芳构化,可分别实际获得一系列相应的3,4-二氢-β-咔啉和β-咔啉。该方法已成功用于Kumujian-C,Eudistomin-U,Norharmane Harmane Harmalan和Isoeudistomin-M的短合成中。
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
Highly diastereoselective synthesis of polycyclic amines via redox neutral C–H functionalization
作者:Chottanahalli S. Pavan Kumar、Kachigere B. Harsha、Nagarakere C. Sandhya、Ajjalli B. Ramesha、Kempegowda Mantelingu、Kanchugarakoppal S. Rangappa
DOI:10.1039/c5nj01706h
日期:——
Synthesis of polycyclic amines was achieved by benzoic acid catalysed reaction of 1-aryl THIQs and 1-aryl trypolines with o-allyl salicylaldehydes through the in situ generated azomethine ylide intermediates that undergo intramolecular [3+2]-cycloadditions with four new stereogenic centers in excellent diastereoselectivities under simple and mild conditions.
Intramolecular Redox-Mannich Reactions: Facile Access to the Tetrahydroprotoberberine Core
作者:Longle Ma、Daniel Seidel
DOI:10.1002/chem.201501667
日期:2015.9.7
α‐CH bond functionalization and reductive N‐alkylation render this transformation redox‐neutral. This redox‐Mannich process provides regioisomers of classic Reinhoudt reaction products as an entry to the tetrahydroprotoberberine core, enabling the synthesis of (±)‐thalictricavine and its epimer. An unusually mild amine‐promoted dealkoxycarbonylation was discovered in the course of these studies.
Mechanistic Studies on Bioinspired Aerobic C–H Oxidation of Amines with an <i>ortho</i>-Quinone Catalyst
作者:Ruipu Zhang、Yan Qin、Long Zhang、Sanzhong Luo
DOI:10.1021/acs.joc.8b02948
日期:2019.3.1
different catalytic pathways were discovered for the reductive half reactions: for primary amines, the reaction was found to proceed via a transamination pathway, while the reactions with secondary amines and tertiary amines proceeded via hydride transfer. We also found that the amine substrates could significantly promote the regeneration of the ortho-quinone catalyst in the oxidative half reaction, in which