140924-91-0Relevant academic research and scientific papers
A convenient synthetic route to partial- cone p-Carboxylatocalix[4]arenes
Fairbairna, Robyn E.,Teatb, Simon J.,Gagnonb, Kevin J.,Dalgarnoa, Scott J.
, p. 516 - 519 (2015)
p-Carboxylatocalix[n]arenes have emerged as useful building blocks for the construction of a diverse range of supramolecular assemblies. A convenient route to a p-carboxylatocalix[4]arene that is locked in a partial-cone conformation is presented. The conformation gives the molecule markedly different topological directionality relative to those previously used in self- And metal-directed assembly studies.
Synthesis of novel calix[4]arenes containing organosilicon groups
Safa, Kazem D.,Oskoei, Yones Mosaei
, p. 26 - 31 (2010)
Metalation of (RSiMe2)3CH (1a R = H, 1b R = Me, 1c R = Ph) with lithium diisopropylamide (LDA) or methyllithium in THF gave organolithium reagents (RSiMe2)3CLi, which reacted with the formylated calixarene (2),
Highly extended styrylstyrylcalix[4]arene assemblies: Synthesis and optical properties
Wong, Man Shing,Li, Zhong Hui,Kwok, Chi Chung
, p. 5719 - 5723 (2000)
Novel highly extended, cone-conformed tetrakis- styrylstyryltetrapropoxycalix[4]arenes and bis- styrylstyryltetrapropoxycalix[4]arenes were synthesized by stereoselective Wadsworth-Emmons reactions. Intramolecular chromophoric interaction of these assemblies resulted in changes to optical properties relative to those of the corresponding monomers with fluorescence enhancement being observed for the assemblies end-capped with methylsulfonyl acceptors. (C) 2000 Elsevier Science Ltd.
Triangular assembly through charged hydrogen bonds in polar solvent
Ho, Yong Lee,Moon, Dohyun,Myoung, Soo Lah,Hong, Jong-In
, p. 9225 - 9228 (2006)
(Chemical Equation Presented) We have demonstrated a triangular assembly driven by 12 charged hydrogen bonds and π-π interactions. This assembly is stable even in polar solvents because of its charged hydrogen-bond nature. Helical arrangement of the complex is confirmed by its crystal structure. A solution structure is assigned to the D3 isomer corresponding to the solid-state structure by temperature-dependent 1H NMR experiments.
Synthesis and crystal structure of p-acylated calix[4]arene ethers
Bajaj, Lukesh,Chawla,Kumar, Satish,Hundal, Geeta,Hundal
, p. 89 - 96 (2014)
C-acylation of calix[n]arenes is an important reaction which has been primarily utilized for their further functionalization to provide conformers with varying shapes, cavity dimensions and molecular receptor characteristics that can bind ionic and neutral species in a selective and specific manner. The length of the alkyl chain at the upper or the lower rim of calixarenes can be adjusted as required to give derivatives which can span the channels and membranes and majorly influence transport phenomenon. As a part of our program to obtain calixarene based derivatives that can span and scan artificial membranes, C-acylation of calix[4]arene has been examined to yield peracylated and partially acylated calixarene ethers. 5,11,17,23-Tetraacetyl-25,26,27,28- tetramethoxycalix[4]arene has been obtained in 80 % yield by treatment of tetramethoxycalix[4]arene with acetyl chloride in the presence of aluminum chloride using dichloromethane as the solvent. The structure was established by the conversion to corresponding phenyl hydrazones and oximes. The tetraacetyltetramethoxycalix[4]arene 2a crystallized in a monoclinic lattice, space group P21/C with a = 10.320(2) A, b = 18.928(4) A, c = 18.421(4) A, β = 95.44(3)o, Z = 4. The corresponding methyl substituted O7 directs inwards towards the cavities of calix[4]arene to give an inward flattened partial cone conformation. Molecular packing shows the presence of intermolecular C-H···O, H-bonding interactions between methyl and methylene hydrogens and oxygens of the acetyl groups.
Upper rim tetrathiafulvalene-bridged calix[4]arenes
Düker, Matthias H.,Gómez, Rafael,Vande Velde, Christophe M.L.,Azov, Vladimir A.
, p. 2881 - 2884 (2011)
The synthesis of novel upper rim calix[4]arene-tetrathiafulvalene conjugates 1a-d has been performed by bridging the tetrachloromethylated calix[4]arene derivative 4 with the corresponding tetrathiafulvalene- dithiolates. The cyclic voltammetry of 1a-d sh
Gilded Chalices: Tetra-aurated Calix[4]arenes
Strasser, Ulf H.,Neumann, Beate,Stammler, Hans-Georg,Berger, Raphael J. F.,Mitzel, Norbert W.
, p. 1061 - 1072 (2014)
Dedicated to Professor Hubert Schmidbaur on the occasion of his 80th birthday 5,11,17,23-Tetrakis(trimethylsilylethynyl)-25,26,27,28-tetra-n-propoxycalix[4]arene (1) was synthesised in two steps starting from 25,26,27,28-tetra-n-propoxycalix[4]arene, and
The selective dealkylations: The formylations of the three easily accessible calix[4]arene conformers immobilized by propyl and isopropyl groups
Yang, Weiping,Guo, Rong,Wang, Wei,Gong, Shuling
, p. 2167 - 2170 (2012)
Formyl groups were introduced to the para positions of the three easily accessible calix[4]arene conformers immobilized by four propyl or isopropyl groups by Duff reaction. Propyl group led to exhaustively formylated products due to the weak steric hinderance effect. While as for the isopropoxy calix[4]arenes, with the increase of steric hinderance, 1,3-alternate conformer gave exhaustively formylated product with no alkyl group dealkylating; partial cone conformer gave the tetraformylated proximal A,B-diether in 1,3-alternate conformation; and cone conformer led to triformylated derivatives accompanied by the selective dealkylations of three or two diametrical alkyl groups. The results indicated that the structures of the products were greatly influenced by the steric hinderance effect of the starting compounds.
A stimulus-responsive shape-persistent micelle bearing a calix[4]arene building block: Reversible pH-dependent transition between spherical and cylindrical forms
Fujii, Shota,Sanada, Yusuke,Nishimura, Tomoki,Akiba, Isamu,Sakurai, Kazuo,Yagi, Naoto,Mylonas, Efstratios
, p. 3092 - 3101 (2012)
A series of cationic calix[4]arene-based lipids with alkyl chains of varying length were newly synthesized, and the ones with propyl and hexyl tails, denoted by CaL[4]C3 and C6, respectively, were found to form spherical micelles at low pH (protonated state of the amine headgroup). Upon deprotonation with increasing pH, CaL[4]C3 showed a sphere-to-cylinder transition, while CaL[4]C6 changed from sphere, to cylinder, to monolayer vesicle. Synchrotron small-angle X-ray scattering (SAXS) patterns from both spherical and cylindrical CaL[4]C3 micelles exhibited a sharp intensity minimum, indicating shape monodispersity. The monodispersity of the CaL[4]C3 spherical micelles was further confirmed by analytical ultracentrifugation (AUC). SAXS, AUC, and static light scattering agreeingly indicated an aggregation number of 6. In contrast, CaL[4]C6 exhibited polydispersity with an average aggregation number of 12. When the number of carbons of the alkyl chain was increased to 9 (CaL[4]C9), cylinder formed at low pH, while at high pH, no clear morphology could be observed. The present results indicate that a very precise combination of tail length, head volume, and rigidity of the building block is required to produce shape-persistent micelles and that the shape-persistence can be maintained upon a structural transition. An attempt to reconstruct a molecular model for the spherical CaL[4]C3 micelle was made with an ab initio shape determining program.
Structure impact in antenna effect of novel upper rim substituted tetra-1,3-diketone calix[4]arenes on Tb(III) green and Yb(III) NIR-luminescence
Zairov, Rustem,Shamsutdinova, Nataliya,Podyachev, Sergey,Sudakova, Svetlana,Gimazetdinova, Gulnaz,Rizvanov, Ildar,Syakaev, Victor,Babaev, Vasily,Amirov, Rustem,Mustafina, Asiya
, p. 2447 - 2455 (2016)
Two novel calix[4]arene macrocyclic ligands functionalized with four 1,3-diketone groups at the upper and hydroxyl (3) or propyloxy-groups (6) at the lower rims were synthesized and characterized using NMR, IR spectroscopy, mass spectrometry, and elemental analysis. UV-vis spectrophotometry and ESI mass spectrometry studies indicate 1:1 complex formation of ligands 3 and 6 with Ln(III) (Ln=Tb, Yb) in alkaline DMF solutions resulted from coordination of Ln(III) with 1,3-diketonate groups. Luminescence study of Ln(III) complexes with 3 and 6 reveals significant difference in antenna effects of their deprotonated forms on both Tb(III)- and Yb(III)-centered luminescence. Comparison of ligand-centered emission for ligands 3 and 6 points to the latter as more efficient antenna for Tb(III) and Yb(III). Different conformational behavior of ligands 3 and 6 in alkaline media is assumed as a reason for the experimentally observed difference in sensitization pathways in Ln(III) complexes with 3 and 6.
