15074-22-3Relevant academic research and scientific papers
Ionic Liquids with Multi-Active Sites Synergistically Catalyzed Metal-Free Transformation of Alcohols Using Dimethyl Carbonate as an Environmental Solvent
Li, Zengmin,Wen, Yating,Wang, Ning,Han, Feng,Li, Ying,Zhuang, Hongfeng,Miao, Chengxia
, p. 3819 - 3826 (2021/08/24)
One of the ultimate goals in organic synthesis is to develop metal-free, efficient and easily separable catalytic system for atom economic organic reactions in an environmental solvent. Direct substitution reaction of alcohols and hydrocarbon compounds is a significant and atom economic method for C?C bond formation. Herein, a metal-free and efficient catalytic system including recyclable pyridine-based ionic liquids with multiple active sites as the catalyst and dimethyl carbonate as the environmentally friendly solvent was developed for atom economic C3 substitution of 4-hydroxycoumarins with alcohols. Primary aromatic alcohols, secondary aliphatic and aromatic alcohols were suitable for the reaction, providing up to 99 % yield. The catalytic system could be easily scaled up to gram-scale with nearly quantitative yield. Coumatetralyl as commercial rodenticide could be prepared directly from commercially available 4-hydroxycoumarin and 1,2,3,4-tetrahydronaphthalen-1-ol. Racemic product derived from the reaction of (R)-1-phenylethanol and 4-hydroxycoumarin indicated the reaction was achieved through an SN1 pathway. The comparison of the activities and acidities of the ionic liquids demonstrated that there was no directly relationship between them. Control experiments showed that the reaction probably proceeded via carbocation, ether intermediate and synergistically promoted effect of hydrogen bonding between the ionic liquid with multi-active sites and substrates.
Tungsten oxides: green and sustainable heterogeneous nanocatalysts for the synthesis of bioactive heterocyclic compounds
Siddiqui,Shaikh, Shoyebmohamad F.,Totawar, Balaji B.,Dumpala, Madhuri,Ubaidullah, Mohd,Thamer, Badr M.,Mane, Rajaram S.,Al-Enizi, Abdullah M.
supporting information, p. 2032 - 2041 (2021/02/26)
Tungsten oxide (WO3) as an efficient heterogeneous catalyst was preparedviaa simple hydrothermal route for the synthesis of a wide range of bioactive heterocyclic compounds. The present investigation deals with the rapid and low-cost synthesis
HFIP Promoted C3 Alkylation of Lawsone and 4-Hydroxycoumarin with Alcohols by Dehydrative Cross-Coupling
Chen, Yixin,Wang, Yurong,Zhong, Rong,Li, Jinshan
, p. 10638 - 10647 (2020/09/23)
An environmentally benign system for the direct alkylation of lawsones and 4-hydroxycoumarins with alcohols in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) is reported. The reaction proceeded smoothly via a dehydrative cross-coupling process by utilizing the unique properties of HFIP. A variety of alkylated products and subsequent one-pot cyclized products (pyranonaphthoquinones and pyranocoumarins) could be obtained in 40-93% yields.
Microwave assisted benzylation of naphthols and 4-hydroxycoumarin under catalyst & solvent free conditions
Dada, Ravikrishna,Singh, Garima,Pareek, Abhishek,Kausar, Saeen,Yaragorla, Srinivasarao
supporting information, p. 3739 - 3742 (2016/07/26)
An expeditious and highly practical, microwave assisted benzylation of naphthols and 4-hydroxycoumarin has been developed under catalyst-free & solvent-free conditions. Alcohols undergo heat induced dehydration to form ethers, which collapse reversibly to form the carbocation which was captured immediately by a suitable nucleophile to furnish the benzylated compounds.
An efficient greener copper triflate-catalyzed C-3 benzylation of 4-hydroxycoumarin and some active methylene compounds
Ganguly, Nemai C.,Chandra, Sumanta
, p. 547 - 555 (2012/10/29)
4-Hydroxycoumarin has been directly benzylated at C-3 position with a good number of secondary benzylic alcohols using copper triflate catalyst (2 mol%) in toluene under reflux. The protocol provides an efficient, expedient and atom-economic access to warfarin and coumatetralyl analogues with potential anticoagulant activity. The protocol has been extended to benzylation of 4-hydroxy-1-methylquinolin-2(1H)-1-one, N-methylbarbiturate and some other active methylene compounds with remarkable success.
Alkylation of 1,3-dicarbonyl compounds with benzylic and propargylic alcohols using Ir-Sn bimetallic catalyst: Synthesis of fully decorated furans and pyrroles
Chatterjee, Paresh Nath,Roy, Sujit
experimental part, p. 4569 - 4577 (2011/07/08)
The heterobimetallic complex [Ir(COD)(SnCl3)Cl(μ-Cl)] 2 catalyzes the direct substitution of hydroxyl groups in benzylic and propargylic alcohols by 1,3-dicarbonyl moiety. In 4-hydroxycoumarin, benzylation and propargylation occurs at the 3-position. Selective propargylation or allenylation takes place depending on the nature of propargylic alcohol. By applying the methodology, multi-substituted furans and pyrroles have been synthesized in good yields.
Condensation of propargylic alcohols with 1,3-dicarbonyl compounds and 4-hydroxycoumarins in ionic liquids (ILs)
Aridoss, Gopalakrishnan,Laali, Kenneth K.
supporting information; experimental part, p. 6859 - 6864 (2012/02/05)
Propargylic alcohols are activated toward 1,3-diketones by Lewis or Br?nsted acidic ionic liquids (ILs) without an added catalyst, but significantly better conversions are achieved with metallic triflates [in particular Sc(OTf)3 and Ln(OTf)sub
Fe(ClO4)3·×H2O-Catalyzed direct C-C bond forming reactions between secondary benzylic alcohols with different types of nucleophiles
Thirupathi, Ponnaboina,Kim, Sung Soo
experimental part, p. 2995 - 3003 (2010/06/14)
Fe(ClO4)3·×H2O as a highly effective catalyst for benzylation of 1,3-dikones, β-ketoesters, 1,3-diesters, electron-rich arenes and heteroarenes and 4-hydroxycoumarin with various benzylic alcohols is described. The usefulness of this procedure is shown by a synthesis of bis-symmetrical triarylmethanes and one step synthesis of an anti-coagulant compound 4-hydroxy-3-(1,2,3,4-tetrahydronaphthalen-1-yl)-2H-chromen-2-one (Coumatetralyl (B)). The advantages of this protocol are broad scope, mild conditions, use of inexpensive catalyst and simplicity of operation since water is the only side product.
Benzylation of β-dicarbonyl compounds and 4-hydroxycoumarin using TMSOTf catalyst: A simple, mild, and efficient method
Theerthagiri, Palani,Lalitha, Appaswami
supporting information; experimental part, p. 5454 - 5458 (2010/11/02)
The direct benzylation of 1,3-dicarbonyl compounds and 4-hydroxycoumarin with a wide variety of benzylic alcohols was achieved using trimethylsilyl trifluoromethanesulfonate as an efficient catalyst. The reaction proceeded under very mild conditions at ro
Tris(pentafluorophenyl)borane-catalyzed alkylation of 1,3-dicarbonyl compounds with benzylic alcohols: Access to oxygenated heterocycles
Reddy, Chada Raji,Vijaykumar, Jonnalagadda,Gree, Rene
experimental part, p. 3715 - 3723 (2010/12/19)
Tris(pentafluorophenyl)borane has found to be an effective catalyst for the alkylation of 1,3-dicarbonyl compounds using benzylic alcohols as alkylating agents. Various 1,3-dicarbonyl compounds reacted cleanly with different benzylic alcohols to provide t
