4636-16-2Relevant academic research and scientific papers
Synthesis of 1,4-Diazepanes and Benzo[ b][1,4]diazepines by a Domino Process Involving the in Situ Generation of an Aza-Nazarov Reagent
Maiti, Swarupananda,Leonardi, Marco,Cores, ángel,Tenti, Giammarco,Ramos, M. Teresa,Villacampa, Mercedes,Menéndez, J. Carlos
, p. 11924 - 11933 (2020)
A step-and atom-economical protocol allowing the synthesis of 1,4-diazepanes and also tetrahydro-and decahydro-1,5-benzodiazepines is described. The method proceeds from very simple starting materials such as 1,2-diamines and alkyl 3-oxohex-5-enoates and can be performed under solvent-free conditions in many instances. The key event of this process was the generation in situ of an aza-Nazarov reagent and its subsequent intramolecular aza-Michael cyclization. An intermolecular version of the reaction was also established and applied to the synthesis of the first example of the pyrrolo[1,2-A][1,5]diazonine framework.
Direct N-alkylation of isatin by halomethyl ketones
Rekhter
, p. 1119 - 1120 (2005)
Solid-phase syntheses are reported for 1-(2-oxoalkyl)indoline-2,3-diones. 2005 Springer Science+Business Media, Inc.
A practical synthesis of α-bromo/iodo/chloroketones from olefins under visible-light irradiation conditions
Wang, Zhihui,Wang, Lei,Wang, Zhiming,Li, Pinhua,Zhang, Yicheng
supporting information, p. 429 - 432 (2020/02/29)
A practical synthesis of α-bromo/iodo/chloroketones from olefins under visible-light irradiation conditions has been developed. In the presence of PhI(OAc)2 as promoter and under ambient conditions, the reactions of styrenes and triiodomethane undergo the transformation smoothly to deliver the corresponding α-iodoketones without additional photocatalyst in good yields under sunlight irradiation. Meanwhile, the reactions of styrenes with tribromomethane and trichloromethane generate the desired α-bromoketones and α-chloroketones in high yields by using Ru(bpy)3Cl2 as a photocatalyst under blue LED (450–455 nm) irradiation.
Methyl Radical Initiated Kharasch and Related Reactions
Tappin, Nicholas D. C.,Renaud, Philippe
supporting information, p. 275 - 282 (2020/12/07)
An improved procedure to run halogen atom and related chalcogen group transfer radical additions is reported. The procedure relies on the thermal decomposition of di-tert-butylhyponitrite (DTBHN), a safer alternative to the explosive diacetyl peroxide, to produce highly reactive methyl radicals that can initiate the chain process. This mode of initiation generates byproducts that are either gaseous (N2) or volatile (acetone and methyl halide) thereby facilitating greatly product purification by either flash column chromatography or distillation. In addition, remarkably simple and mild reaction conditions (refluxing EtOAc during 30 minutes under normal atmosphere) and a low excess of the radical precursor reagent (2 equivalents) make this protocol particularly attractive for preparative synthetic applications. This initiation procedure has been demonstrated with a broad scope since it works efficiently to add a range of electrophilic radicals generated from iodides, bromides, selenides and xanthates over a range of unactivated terminal alkenes. A diverse set of radical trap substrates exemplifies a broad functional group tolerance. Finally, di-tert-butyl peroxyoxalate (DTBPO) is also demonstrated as alternative source of tert-butoxyl radicals to initiate these reactions under identical conditions which gives gaseous by-products (CO2). (Figure presented.).
Direct Trifluoromethoxylation without OCF3-Carrier through In Situ Generation of Fluorophosgene
Donnard, Morgan,Guérin, Thomas,Hanquet, Gilles,Leroux, Frédéric R.,Panossian, Armen,Saiter, Jérémy
supporting information, p. 3139 - 3147 (2021/06/26)
Owing to the high interest in the OCF3 group for pharmaceutical and agrochemical applications, trifluoromethoxylation received great attention in the last years with several new methods for this approach towards OCF3-comprising compounds. Yet, it most often requires the beforehand preparation of specific F3CO? transfer reagents, which can be toxic, expensive, unstable, and/or generate undesired side-products upon consumption. To circumvent this, the in-situ generation of gaseous fluorophosgene from triphosgene, its conversion by fluoride into the OCF3 anion, and the direct use of the latter in nucleophilic substitutions is an appealing strategy, which, although recently approached, has not been fully exploited. We disclose herein our efforts towards this aim.
Construction and regulation of imidazo[1,5-a]pyridines with AIE characteristics via iodine mediated Csp2?H or Csp?H amination
Zhang, Jun,She, Mengyao,Liu, Lang,Liu, Mengdi,Wang, Zhaohui,Liu, Hua,Sun, Wei,Liu, Xiaogang,Liu, Ping,Zhang, Shengyong,Li, Jianli
supporting information, p. 3083 - 3086 (2021/06/28)
The widespread applications of aggregation-induced emission luminogens (AIEgens) inspire the creation of AIEgens with novel structures and functionalities. In this work, we focused on the direct and efficient synthesis of a new type of AIEgens, imidazo[1,5-a]pyridicne derivatives, via iodine mediated cascade oxidative Csp2–H or Csp–H amination route from phenylacetylene or styrenes under mild conditions. The resulted compounds showed excellent AIE characteristics with tunable maximum emissions, attractive bioimaging performance, and potential anti-inflammatory activity, which exert broad application prospects in material, biology, medicine, and other relevant areas.
Direct Synthesis of 4-Aryl-1,2,3-triazoles via I2-Promoted Cyclization under Metal- And Azide-Free Conditions
Geng, Xiao,Huang, Chun,Wang, Li-Sheng,Wu, An-Xin,Wu, Yan-Dong,Yu, Xiao-Xiao,Zhao, Peng,Zhou, You
, p. 13664 - 13672 (2021/10/01)
We herein report an iodine-mediated formal [2 + 2 + 1] cyclization of methyl ketones, p-toluenesulfonyl hydrazines, and 1-aminopyridinium iodide for preparation of 4-aryl-NH-1,2,3-triazoles under metal- and azide-free conditions. Notably, this is achieved
One pot synthesis of α-N-heteroaryl ketone derivatives from aryl ketones using aqueous NaICl2
Ghodse, Shrikant M.,Hatvate, Navnath T.,Telvekar, Vikas N.
, (2021/12/08)
A simple and efficient method for the synthesis of α-heteroaryl ketones from aryl ketones and amine using aqueous sodium dichloroiodate is established. This method is mild, operationally simple, has a short reaction time, and easy workup procedure to afford the corresponding α-N-heteroaryl ketone derivatives in moderate to good yield.
V2O5@TiO2 Catalyzed Green and Selective Oxidation of Alcohols, Alkylbenzenes and Styrenes to Carbonyls
Upadhyay, Rahul,Kumar, Shashi,Maurya, Sushil K.
, p. 3594 - 3600 (2021/07/02)
The versatile application of different functional groups such as alcohols (1° and 2°), alkyl arenes, and (aryl)olefins to construct carbon-oxygen bond via oxidation is an area of intense research. Here, we report a reusable heterogeneous V2O5@TiO2 catalyzed selective oxidation of various functionalities utilizing different mild and eco-compatible oxidants under greener reaction conditions. The method was successfully applied for the alcohol oxidation, oxidative scission of styrenes, and benzylic C?H oxidation to their corresponding aldehydes and ketones. The utilization of mild and eco-friendly oxidizing reagents such as K2S2O8, H2O2 (30 % aq.), TBHP (70 % aq.), broad substrate scope, gram-scale synthesis, and catalyst recyclability are notable features of the developed protocol.
1,2-Dibromoethane and KI mediated α-acyloxylation of ketones with carboxylic acids
Wang, Xujie,Li, Gangsheng,Yang, Yanan,Jiang, Jianshuang,Feng, Ziming,Zhang, Peicheng
supporting information, p. 711 - 714 (2019/09/30)
The 1,2-dibromoethane- and KI-mediated α-acyloxylation of ketones is reported in moderate to good yield without the use of transition metals and strong oxidants. Various acids are well tolerated with wide functional group compatibility. An 1,2-dibromoethane- and KI-catalysed reaction mechanism is proposed based on the results of control experiments.
