673-22-3Relevant articles and documents
Formylation of activated arenes by phenyl formate: Implications for the mechanism of the Fries rearrangement of aryl formates
Bagno, Alessandro,Kantiehner, Willi,Saielli, Giacomo
, p. 682 - 687 (2008)
We present an NMR and DFT investigation of the reaction of phenyl formate with 3-methoxyphenol and 3,5-dimethoxyphenol with excess BCl3. The products obtained (3-methoxy- and 3,5-dimethoxy-salicylaldehyde, respectively) are the same as those resulting from the Fries rearrangement of 3-methoxy- and 3,5-dimethoxy-phenyl formate. These results represent a novel regioselective synthetic route to aromatic aldehydes, using phenyl formate as a source of formylating agent. They also unambiguously prove that the Fries rearrangement of aryl formates (that we recently investigated in J. Org. Chem. 71, 9331-9340, 2006) is intermolecular: the intermediate formyl chloride is released in situ and, in turn, it formylates the intermediate dichloroborate ester of 3-methoxy- and 3,5-dimethoxy-phenol in a second independent step. The -BCl2 moiety bound to the aryl oxygen of the substituted phenol interacts with the formyl chloride strongly favouring the ortho substitution. Copyright
Phosphine-catalyzed sequential (2+3)/(2+4) annulation of γ-vinyl allenoates: Access to the synthesis of chromeno[4,3-: B] pyrroles
Huang, You,Li, Xiaohu
supporting information, p. 9934 - 9937 (2021/10/12)
A phosphine-catalyzed cascade (2+3)/(2+4) cyclization reaction of γ-vinyl allenoates with aldimine esters has been developed to provide a series of chromeno[4,3-b]pyrrole derivatives that contain three contiguous stereogenic centers. The method gives a good yield, excellent chemoselectivity and diastereoselectivity under mild conditions.
Anchimerically Assisted Selective Cleavage of Acid-Labile Aryl Alkyl Ethers by Aluminum Triiodide and N, N-Dimethylformamide Dimethyl Acetal
Sang, Dayong,Yue, Huaxin,Zhao, Zhengdong,Yang, Pengtao,Tian, Juan
, p. 6429 - 6440 (2020/07/14)
Aluminum triiodide is harnessed by N,N-dimethylformamide dimethyl acetal (DMF-DMA) for the selective cleavage of ethers via neighboring group participation. Various acid-labile functional groups, including carboxylate, allyl, tert-butyldimethylsilyl (TBS), and tert-butoxycarbonyl (Boc), suffer the conditions intact. The method offers an efficient approach to cleaving catechol monoalkyl ethers and to uncovering phenols from acetal-type protecting groups such as methoxymethyl (MOM), methoxyethoxymethyl (MEM), and tetrahydropyranyl (THP) chemoselectively.
Selective ether bond breaking method of aryl alkyl ether
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Paragraph 0166-0170, (2020/09/16)
The invention discloses a selective aryl alkyl ether cracking method, which comprises that aryl alkyl ether, aluminum iodide and an additive are subjected to a selective ether bond cleavage reaction in an organic solvent at a temperature of -20 DEG C to a reflux temperature to generate phenol and derivatives thereof. The method is mild in condition and simple and convenient to operate, is suitablefor cracking aryl alkyl ether containing o-hydroxyl and o-carbonyl and acetal ether, and can also be used for removing tertiary carbon hydroxyl protecting groups with higher steric hindrance, such astriphenylmethyl, tertiary butyl and the like.
Catalytic oxidation of alcohols and alkyl benzenes to carbonyls using Fe3O4?SiO2?(TEMPO)-: Co -(Chlorophyll-CoIII) as a bi-functional, self-co-oxidant nanocatalyst
Hamah-Ameen, Baram Ahmed,Kazemnejadi, Milad,Mahmoudi, Boshra,Rostami, Amin
, p. 6600 - 6613 (2020/11/16)
Chlorophyll b was extracted from heliotropium europaeum plant, demetalated, allylated and grafted to acrylated TEMPO through a copolymerization protocol. Then, the chlorophyll monomers were coordinated to Co ions, immobilized on magnetic nanoparticles and the resulting hybrid was used as a powerful catalyst for a variety of oxidation reactions. By using the present method, oxidation of benzylic alcohols and alkyl benzenes to carbonyls was accomplished in water under aerobic conditions. Moreover, direct oxidation of alcohols to carboxylic acids was performed by adding NaOCl to the mixture. All entries were oxidized to the corresponding desired product with high to excellent yields and up to 97% selectivity. The catalyst was thoroughly characterized by CV, TGA, VSM, XRD, XPS, DLS, FE-SEM, TEM, UV-Vis, EDX, and BET analyses. The activity of the catalyst was investigated by applying various components of the catalyst to the oxidation model separately. The reasonable mechanisms are suggested based on the cooperation between the TEMPO groups and cobalt(iii) (or Co(iv)) sites on the catalyst. The catalyst could be recovered and reused for at least 7 consecutive recycles without any considerable reactivity loss. This journal is
Polymer-incarcerated palladium-catalyzed facile: In situ carbonylation for the synthesis of aryl aldehydes and diaryl ketones using CO surrogates under ambient conditions
Dey, Tusar Kanto,Basu, Priyanka,Riyajuddin, Sk,Ghosh, Aniruddha,Ghosh, Kaushik,Manirul Islam, Sk
, p. 9802 - 9814 (2019/07/04)
In this existing work, an efficient polymer-supported palladium catalyst, a furfurylamine-functionalized Merrifield complex of palladium [Pd@(Merf-FA)], was synthesized and characterized, showing excellent catalytic activity towards in situ carbonylation reactions using carbon monoxide surrogates like formic acid and chloroform. Herein, we examined the catalytic activity of the Pd@(Merf-FA) catalyst for the formylation of aryl iodides and carbonylative Suzuki-Miyaura coupling reactions. The Pd@(Merf-FA) catalyst was systematically characterized by several techniques like HRTEM, elemental mapping, PXRD, TGA-DTA, FESEM, UV-vis, EDAX, CHN and AAS analysis. The catalyst is highly recyclable, able to be recycled up to six times without showing any significant decrease in catalytic activity. The [Pd@(Merf-FA)] catalyst proved to be more efficient compared to the corresponding homogeneous palladium catalyst. In addition, the leaching experiment of the synthesized catalyst was studied, which showed that negligible leaching of metal occurred from the polymeric support.
Fe3O4@SiO2@Im[Cl]Mn(III)-complex as a highly efficient magnetically recoverable nanocatalyst for selective oxidation of alcohol to imine and oxime
Kazemnejadi, Milad,Alavi, Seyyedeh Ameneh,Rezazadeh, Zinat,Nasseri, Mohammad Ali,Allahresani, Ali,Esmaeilpour, Mohsen
, p. 230 - 249 (2019/03/28)
An efficient and environmentally friendly oxidation process for the one-pot preparation of oxime, imine and carbonyl compounds through alcohol oxidation in the presence of H2O2 and/or O2 have been developed by a melamine-Mn(III) Schiff base complex supported on Fe3O4@SiO2–Cl nanoparticles, named as Fe3O4@SiO2@Im[Cl]Mn(III)-complex nanocomposite, at room temperature. Direct oxidation of alcohol to carboxylic acid was performed using the catalyst in the presence of molecular O2 at room temperature in a different approach. The oxidation products were obtained with excellent yields and high TOFs. The properties of the catalyst were characterized by Fourier transform infrared spectroscopy (FTIR), elemental analysis (C, H, N), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), inductive coupled plasma (ICP), cyclic voltammetry (CV), nuclear magnetic resonance (1H & 13C NMR), vibration sample magnetometer (VSM), Brunauer– Emmett–Teller (BET) and differential pulse voltammetry (DPV) analyses. The mechanism of the oxidation processes was investigated for the both H2O2 and O2 oxidants. The role of the imidazolium moiety in the catalyst as a secondary functionality was investigated. Chemoselectivity behavior of the catalyst was studied by some combinations. The catalyst could be recycled from the reaction mixture by a simple external magnet and reused for several times without any considerable reactivity loss.
Phosphine-Catalyzed [3+2] Annulation of β-Sulfonamido-Substituted Enones with Sulfamate-Derived Cyclic Imines
Shi, Wangyu,Zhou, Leijie,Mao, Biming,Wang, Qijun,Wang, Chang,Zhang, Cheng,Li, Xuefeng,Xiao, Yumei,Guo, Hongchao
supporting information, p. 679 - 685 (2019/01/24)
Phosphine-catalyzed [3+2] annulation of β-sulfonamido-substituted enones and sulfamate-derived cyclic imines has been developed, giving a series of imidazoline derivatives in moderate to excellent yields with good to excellent diastereoselectivities. A scale-up reaction worked well under mild reaction conditions. A possible mechanism was proposed on the basis of the results obtained.
3-(Triflyloxy)benzynes Enable the Regiocontrolled Cycloaddition of Cyclic Ureas to Synthesize 1,4-Benzodiazepine Derivatives
Kaneko, Hideki,Ikawa, Takashi,Yamamoto, Yuta,Arulmozhiraja, Sundaram,Tokiwa, Hiroaki,Akai, Shuji
supporting information, p. 943 - 948 (2018/02/26)
A versatile synthesis of 1,4-benzodiazepine derivatives through the reaction of various 3-(trifluoromethanesulfonyloxy)benzynes with N -(p -toluenesulfonyl)imidazolidin-2-ones is reported. This reaction system provides a 1,4-benzodiazepine bearing a trifluoromethanesulfonyloxy group as a single regioisomer among the four possible regioisomers.
Origin of green photoluminescence in four-ring bent-core molecules with ESIPT, selective sensing of zinc ions by turn-on emission and their liquid crystal properties
Gude, Venkatesh,Rout, Duttanjali,Panigrahi, Mruganka Kumar,Biradha, Kumar
, p. 1386 - 1395 (2018/10/21)
Fluorescent four-ring symmetrical/unsymmetrical molecules containing alkyl chains of a varied number of-CH2-groups with a bent-core have been synthesized to explore their liquid crystalline (LC) and photophysical properties. Some of these molecules depending upon their alkyl chain length were found to exhibit B1 and B7 liquid crystalline phases and are characterized by various analytical techniques such as FT-IR,1H NMR, mass, POM, DSC, single crystal XRD, etc. Crystal structure determination reveals the hydrogen bonded enol form of these molecules with non-planar bent-molecular geometry. Intramolecular hydrogen bonding was found to play an important role in the stabilization of these molecules and in the origin of their green photoluminescence (GPL). The photo-physical experimental results through various control experiments clearly demonstrate that the origin of the large Stokes shifted GPL of these molecules can be attributed to the excited state intramolecular proton transfer (ESIPT) process. The formation of various types of anionic species and their stability were explored through steady-state and time-resolved fluorescence measurements. These compounds are found to be good turn-on PL probes in the selective detection of zinc ions at the micromolar level. Upon binding of zinc ions with the bent-core molecule, the structural changes have been investigated through NMR spectroscopy.
