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Abstract A green and efficient methodology has been developed for the direct conversion of aryl aldehydes to the corresponding tert-butyl peresters. The reaction has been carried out in absence of any solvent and the sunlight is used as the green source of energy. In this reaction tetrabutylammonium iodide (TBAI) acts as the mild organo catalyst and tert-butyl hydroperoxide (TBHP) serve as the source of tert-butyl group. 相似文献
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An efficient and mild method for tetrahydropyranylation of alcohols and their detetrahydropranylation using NH4Cl is described. This protocol provides a useful alternative tetrahydropyranylation of alcohols and their deprotection at different pH. 相似文献
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The synthesis of carbonyl compounds by oxidation of alcohols is a key reaction in organic synthesis. Such oxidations are typically conducted using catalysts featuring toxic metals and hazardous organic solvents. Considering green and sustainable chemistry, a copper(II) complex of sulfonated 2-quinoxalinol salen (sulfosalqu) has been characterized as an efficient catalyst for the selective oxidation of propargylic, benzylic, and allylic alcohols to the corresponding carbonyl compounds in water when in combination with the oxidant tert-butyl hydroperoxide. The reactions proceed under mild conditions (70 °C in water) to produce yields up to 99% with only 1 mol % of catalyst loading. This reaction constitutes of a rare example of propargylic alcohol oxidation in water, and it makes this process greener by eliminating the use of hazardous organic solvents. Excellent selectivity was achieved with this catalytic protocol for the oxidation of propargylic, benzylic, and allylic alcohols over aliphatic alcohols. The alcohol oxidation is thought to go through a radical pathway. 相似文献
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Gareth J. Rowlands Author Vitae 《Tetrahedron》2010,66(9):1593-501
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Graphene is scientifically and commercially important because of its unique molecular structure which is monoatomic in thickness, rigorously two-dimensional and highly conjugated. Consequently, graphene exhibits exceptional electrical, optical, thermal and mechanical properties. Herein, we critically discuss the surface modification of graphene, the specific advantages that graphene-based materials can provide over other materials in sensor research and their related chemical and electrochemical properties. Furthermore, we describe the latest developments in the use of these materials for sensing technology, including chemical sensors and biosensors and their applications in security, environmental safety and diseases detection and diagnosis. 相似文献
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Ruthenium(II) perchlorate complexes, [Ru(dppm)3(ClO4)]ClO4 1, [Ru(dppe)3(ClO4)]ClO4 2, and [Ru(dpae)3(ClO4)]ClO4 3, catalyse the selective homogeneous oxidation of alkenes with TBHP and H2O2 as oxidizing agents. Oxidation of cyclohexene with TBHP gave 2-cyclohexene-1-ol, 2-cyclohexenone and 1-(tert-butylperoxy)-2-cyclohexene. The homogeneous liquid phase oxidation of cyclohexene with TBHP shows appreciable solvent effect. Styrene on oxidation with TBHP gave benzaldehyde as the major product and styrene oxide as the minor product. Oxidation with H2O2 is radical-initiated and gives low conversion to products. TBHP and H2O2 are compared for their oxidizing ability and TBHP is more effective than H2O2 as an oxidizing agent. Linear and long chain alkenes are not efficiently oxidized. Cyclooctene and trans-stilbene are oxidized to the corresponding epoxides. 相似文献
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The ruthenium complex Ru(terpyridine)(2,6‐pyridinedicarboxylate) was successfully grafted onto MCM‐41 using a multi‐step grafting method. The immobilized ruthenium complex was characterized thoroughly using Fourier transform infrared, Raman, UV–visible diffuse reflectance and energy‐dispersive X‐ray spectroscopies, X‐ray diffraction, N2 adsorption, scanning electron microscopy, thermogravimetric analysis and inductively coupled plasma analysis. This immobilized ruthenium complex showed excellent performance in the oxidation of various secondary alcohols to their corresponding ketones with tert‐butyl hydroperoxide as oxidant under solvent‐free conditions, and had the advantages of easy recovery and good reusability. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Tert‐butyl hydroperoxide‐promoted guanylation of amines with benzoylthioureas: Mechanistic insights by HRMS and 1H NMR
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Henrique Esteves Tiago Oliveira Brito Renato Ribeiro‐Viana Ângelo de Fátima Fernando Macedo Jr. 《Journal of Physical Organic Chemistry》2017,30(12)
Herein, we present a mechanistic study on tert‐butyl hydroperoxide‐promoted guanylation of thioureas by monitoring short lifetime intermediates using electrospray ionisation/time‐of‐flight high resolution mass spectrometry (ESI‐Q‐TOF HRMS). Moreover, 1H nuclear magnetic resonance data allowed us to access kinetic parameters for the main species involved which, allied to the HRMS results, furnished valuable insights over previously reported observations. The results suggested an addition/elimination mechanism involving the aminoiminomethanesulphinic acid, RNC(SO2H)NHR′, and the nucleophilic amine as the main pathway to yield the guanidine. Noteworthy, benzoylthiourea consumption rate presented a nonlinear kinetic behaviour, while tBuOOH and the nucleophilic amine consumptions were found to follow second‐order kinetics. 相似文献
10.
《Tetrahedron》2014,70(52):9819-9827
The reaction of (hetero)aromatic aldehydes or cinnamaldehyde with di-/multi-ethers in the presence of Bu4NI and tert-butyl hydroperoxide generated corresponding α-acyloxy ethers. Reactions between (hetero)aromatic aldehydes or cyclohexanecarbaldehyde with arylalkyl ketones under similar conditions resulted in α-acyloxy ketones. Collectively, Bu4NI-catalyzed α-acyloxylation reactions exhibit a broad scope of substrates and a high compatibility with functional groups. 相似文献