15547-67-8Relevant academic research and scientific papers
Reusable, homogeneous water soluble photoredox catalyzed oxidative dehydrogenation of N-heterocycles in a biphasic system: Application to the synthesis of biologically active natural products
Abinaya, R.,Baskar, B.,Mariappan, M.,Prasanth, Arun,Sridhar, R.,Srinath, S.
, p. 2575 - 2587 (2020/05/13)
Herein, a simple and efficient method for the oxidative dehydrogenation (ODH) of tetrahydro-β-carbolines, indolines and tetrahydro-(iso)quinolines is described using a reusable, homogeneous cobalt-phthalocyanine photoredox catalyst in a biphasic medium. A biphasic system offers an advantage of easy separation of the product and an efficient reusability of the homogeneous photoredox catalyst. Also, the current system significantly helps to overcome the solubility issue of 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 eudistomin U, norharmane, and harmane and precursors to perlolyrine and flazin. Without isolation and purification, the catalyst solution can be reused up to 5 times with almost comparable reactivity. Furthermore, the efficiency of the reaction was demonstrated on a gram scale. To the best of our knowledge, this is the first report on ODH reactions using a non noble, reusable and homogeneous cobalt photoredox catalyst under environmentally friendly conditions.
Cerium Chloride Catalyzed, 2-Iodoxybenzoic Acid Mediated Oxidative Dehydrogenation of Multiple Heterocycles at Room Temperature
Hati, Santanu,Sen, Subhabrata
supporting information, p. 1277 - 1280 (2017/03/17)
Catalytic cerium chloride was found to activate 2-iodoxybenzoic acid (IBX) for the oxidative dehydrogenation of tetrahydroisoquinolines, tetrahydro-β-carbolines, and thiazolidines to their dehydrogenated and aromatic forms at room temperature in moderate to excellent yields. The robustness of the protocol was demonstrated by scaling up the reactions to multigram quantities.
Facile synthesis of substituted isoquinolines
Chang, Meng-Yang,Wu, Ming-Hao,Lee, Nein-Chia,Lee, Ming-Fang
, p. 2125 - 2128 (2012/07/14)
A facile three-step protocol toward methoxy isoquinolines 7 starting with substituted 2-allylbenzaldehydes 9 was described. The overall synthetic process of skeleton 7 was carried out using the Grignard addition, PCC-oxidation, and one-pot oxidative cleavage of the olefinic group of skeleton 9 with OsO 4-NaIO4 followed by the condensation of the resulting 1,5-dicarbonyl compounds with NH4OAc. Skeleton 9 was prepared in high yield via the known Claisen rearrangement of skeleton 8 and O-methylation. Papaverine 2 is also synthesized via the simple three-step synthetic protocol.
Strategies and synthetic methods directed toward the preparation of libraries of substituted isoquinolines
Awuah, Emelia,Capretta, Alfredo
supporting information; experimental part, p. 5627 - 5634 (2010/11/03)
Strategies for the production of substituted isoquinoline libraries were developed and explored. Routes involving microwave-assisted variants of the Bischler-Napieralski or Pictet-Spengler reaction allowed for cyclization of substituted β-arylethylamine derivatives. The dihydroisoquinolines and tetrahydroisoquinolines thus generated could then be oxidized to their corresponding isoquinoline analogues. An alternate strategy, however, involving the preparation and activation of isoquinolin-1(2H)-ones is demonstrated to be a more practical, rapid, and efficient route to C1- and C4-substituted isoquinoline libraries.
Efficient and practical one-pot conversions of n- tosyltetrahydroisoquinolines into isoquinolines and of N-tosyltetrahydro-β- carbolines into β-carbolines through tandem β-elimination and aromatization
Dong, Jing,Shi, Xiao-Xin,Yan, Jing-Jing,Xing, Jing,Zhang, Qiang,Xiao, Sen
experimental part, p. 6987 - 6992 (2011/02/24)
An efficient, practical, and general method for conversions of N-tosyltetrahydroisoquinolines (N-tosyl-THIQs) into isoquinolines and of N-tosyltetrahydro-β-carbolines (N-tosyl-THBCs) into β-carbolines is described. Treatment of N-tosyl-THIQs or N-tosyl-THBCs with base in dimethyl sulfoxide afforded dihydroisoquinolines or dihydro-β-carbolines as intermediates, and these were then oxidized in situ by molecular oxygen to furnish isoquinolines or β-carbolines in good to high yields. Both one-pot conversions occurred through tandem β-elimination and aromatization. An efficient method for conversions ofN-tosyltetrahydroisoquinolines (N-tosyl-THIQs) and N-tosyltetrahydro-β-carbolines (N-tosyl-THBCs) into isoquinolines and β-carbolines is described. Treatment ofN-tosyl-THIQs or N-tosyl-THBCs with base affords dihydroisoquinolines or dihydro-β- carbolines. These can be oxidized in situ by molecular oxygen to furnish isoquinolines or β-carbolines. Copyright
An alternative to pictet-gams reaction triggered by hendrickson reagent: Isoquinolines and β-carbolines from amides
Wu, Mengde,Wang, Shaozhong
experimental part, p. 587 - 592 (2010/04/24)
The Hendrickson reagent derived from triflic anhydride and triphenylphosphine oxide exhibited high oxophilicity and induced the intramolecular cyclization of β-arylethylamides perfectly. Thus, a one-pot protocol to access isoquinoline and β-carboline was developed involving cyclization followed by oxidative aromatization. Georg Thieme Verlag Stuttgart · New York.
Structure-based approach to falcipain-2 inhibitors: Synthesis and biological evaluation of 1,6,7-Trisubstituted dihydroisoquinolines and isoquinolines
Batra, Sanjay,Sabnis, Yogesh A.,Rosenthal, Philip J.,Avery, Mitchell A.
, p. 2293 - 2299 (2007/10/03)
1,4,7-Trisubstituted isoquinolines were designed, synthesized and evaluated for their inhibition against Plasmodium falciparum cysteine protease falcipain-2. The 1-benzyloxyphenyl-dihydroisoquinoline and -isoquinoline derivatives were found to exhibit better activity against falcipain-2 than their corresponding 1-hydroxyphenyl or 1-methoxyphenyl analogues. The docking scores correlate with the IC50 values of compounds and give a high coefficient correlation of 0.94.
