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Carmen Coll Elena Aznar Ramón Martínez‐Máñez Prof. M. Dolores Marcos Dr. Félix Sancenón Dr. Juan Soto Dr. Pedro Amorós Joan Cano Dr. Eliseo Ruiz Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(33):10048-10061
We report the preparation of a MCM‐41 mesoporous material that contains the dye [Ru(bipy)3]Cl2 (bipy=bipyridine) inside the mesopores and functionalised with suitable binding groups at the entrance of the pores. Solids S1 – S3 were obtained by the reaction of the mesoporous material with N‐methyl‐N′‐propyltrimethoxysilylimidazolium chloride, N‐phenyl‐N′‐[3‐(trimethoxysilyl)propyl]thiourea, or N‐phenyl‐N′‐[3‐(trimethoxysilyl)propyl]urea, respectively. A study of the dye delivery of these systems in buffered water (pH 7.0, 2‐[4‐(2‐hydroxyethyl)piperazin‐1‐yl]ethanesulfonic acid (HEPES), 10?3 mol dm?3) in the presence of a family of carboxylate ions was carried out. In the interaction of the anions with the surface of the solids, the response depends on the characteristics of the binding groups (i.e., imidazolium, urea and thiourea) at the pore outlets and their specific interaction with the corresponding anion. The interaction of long‐chain carboxylate ions with the binding sites at the surface of the solids resulted in a remarkable inhibition of the delivery of the dye. This inhibition was observed clearly for the dodecanoate anion, whereas the octanoate, decanoate, cholate, deoxycholate, glycodeoxycholate and taurocholate anions induced a certain pore blockage that varied according to the solid studied. The interaction of smaller anions, such as acetate, butanoate, hexanoate and octanoate, with the solids had no effect on the dye release process. The possible use of the gating system for the chromo‐fluorogenic detection of anionic surfactants through selective dye delivery inhibition was also explored. Molecular dynamic simulations that use force‐field methods have been made to theoretically study the capping carboxylate mechanism. The calculations are in agreement with the experimental results, thus allowing a representation of the dye delivery inhibition in the presence of long‐chain carboxylate ions. 相似文献
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Singh Swati Bawitlung Laldingngheti Singh Munmun Kumar Chauhan Amit Padalia Rajendra Chandra Pal Anirban Verma Ram Swaroop 《Chemistry of Natural Compounds》2022,58(1):161-162
Chemistry of Natural Compounds - 相似文献
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Lydia A. Panther Dr. Daniel P. Guest Dr. Andrew McGown Hugo Emerit Dr. Raysa Khan Tareque Dr. Arathy Jose Mr. Chris M. Dadswell Dr. Simon J. Coles Dr. Graham J. Tizzard Dr. Ramón González-Méndez Dr. Charles A. I. Goodall Prof. Mark C. Bagley Prof. John Spencer Dr. Barnaby W. Greenland 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(49):e202201444
Solvent-free synthesis by using a vibratory ball mill (VBM) offers the chance to access new chemical reactivity, whilst reducing solvent waste and minimising reaction times. Herein, we report the core functionalisation of N,N’-bis(2-ethylhexyl)-2,6-dibromo-1,4,5,8-naphthalenetetracarboxylic acid (Br2-NDI) by using Suzuki, Sonogashira and Buchwald–Hartwig coupling reactions. The products of these reactions are important building blocks in many areas of organic electronics including organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs) and organic photovoltaic cells (OPVCs). The reactions proceed in as little as 1 h, use commercially available palladium sources (frequently Pd(OAc)2) and are tolerant to air and atmospheric moisture. Furthermore, the real-world potential of this green VBM protocol is demonstrated by the double Suzuki coupling of a monobromo(NDI) residue to a bis(thiophene) pinacol ester. The resulting dimeric NDI species has been demonstrated to behave as an electron acceptor in functioning OPVCs. 相似文献
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Vianey Vasquez-Ruiz M. Ángeles Ramírez-Cisneros Maria Yolanda Rios 《Magnetic resonance in chemistry : MRC》2022,60(3):275-358
Cedrela genus, a member of the Meliaceae family, presents both chemical characteristics associated with and those that distinguish it from the rest of its members. The presence of triterpenes and limonoids is the characteristic of the Meliaceae family, but the class and type of these chemical constituents are distinctive for each genus. Cedrela includes cycloartane, ursane, oleanane, tirucallane, butyrospermane, and apotirucallane triterpenes, and its limonoids belongs to six class and nine types, known as class Ia-type havanensines, class Ib-type delevoyin, class II-type gedunin, class IIIb-type andirobin, class IIIg-type mexicanolide, class IVa-type evoludone, class Va-type obacunol, class V-type limonin, and class VIII. Each of these structural arrangements includes specific traits, defined by their biosynthetic origin, which can be established by means of structural elucidation techniques, particularly 1H and 13C NMR, which assisted by 2D NMR techniques, allowing to deduce their structures unequivocally. The constant presence of these skeletal arrangements in Cedrela ensures that they are its chemophenetic markers and their recurrence is an important criterion for their identity. This review is a compilation of the occurrence of triterpenes and limonoids in Cedrela genus, detailing their biosynthetic association and collecting and organizing their NMR data, with the purpose of facilitating its location, analysis, and use in the phytochemical study of species from this genus. 相似文献
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Summary Novel bimetallic alkoxides of copper(II) of the type Cu[M(OPr-i)6]2 (M = Nb or Ta) have been synthesised by the interaction of CuCl2 (1 mol) with K[M(OPr-i)6] (2 mol). These bimetallic isopropoxides undergo facile alcohol interchange with primary alcohols such as MeOH, EtOH,n-PrOH andn-BuOH. However, witht-BuOH, the reaction cannot be driven to completion even under prolonged continuous azeotropic fractionation of the liberatedi-PrOH and the final product corresponded in analysis to Cu[Ta(OPr-i)2(OBu-t)4]2.I.r., electronic and electron spin resonance spectral and magnetic susceptibility measurements indicate a distorted octahedralD
4h geometry for copper(II) in these bimetallic alkoxides. 相似文献