• Journal of Photoscience
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• v.11 no.32
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• pp.71-74
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• 2004

The macrocycle L exhibited a switch on-off behavior through the fluorescent responses by aromatic imine molecule 1 (X=H) / trifluoroacetic acid (TFA). In the 'switch on' state, it was supposed that the aromatic imine molecule 1 is in the cavity of macrocycle L and a photoinduced electron transfer (PET) from the nitrogen of azacrown part to the anthryl group is inhibited by the interaction between the aromatic imine molecule 1 and the azacrown part of macrocycle L. In the 'switch off' state, it was supposed that the protonated imine molecule 1 is induced by the continuous addition of TFA and a repulsion between the protonated azacrown part and the protonated imine molecule 1 is occurred. It was considered that this process induces the intermolecular PET from the protonated imine molecule 1 to the anthryl group of macrocycle L because of a proximity effect between the anthryl group and the protonated imine molecule 1. From the investigation of the transient emission decay curve, the macrocycle L showed three components (3.45 ns (79.72%), 0.61 ns (14.53%), and 0.10 ns (5.75%). When the imine molecule 1 was added in the macrocycle L as molar ratio=1:1, the first main component showed a little longer lifetime as 3.68 ns (82.75%) although the other two components were similar as 0.64 ns (14.28%) and 0.08 ns (2.96%). On the contrary, when the imine molecule 3 (X=C1) was added in the macrocycle L as molar ratio=l:1, all the three components were decreased such as 3.27 ns (69.83%), 0.44 ns (13.24%), and 0.06 ns (16.93%). The fluorescent pH titration of macrocycle L was carried out from pH=3 to pH=9. The macrocycle L and C $U^{2+}$- macrocycle L complex were intersected at about pH=5, while the E $u^{3+}$ -macrocycle L complex was intersected at about pH=5.5. In addtion, we investigated the fluorescence change of macrocycle L as a function of the substituent constant ($\sigma$$_{p}$$^{o}$) showing in the para-substituent with electron withdrawing groups (X=F, Cl) and electron donating groups (X=C $H_3$, OC $H_3$, N(C $H_3$)$_2$), respectively, as well as non-substituent (X=H).).ctively, as well as non-substituent (X=H).

• Journal of Photoscience
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• v.11 no.1
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• pp.7-9
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• 2004

The synthesized macrocycle L was found to be a smart fluorescent receptor which distinguishable efficiently from various neutral molecules with the functional groups such as the electron donating (X =$CH_3$, N($CH_3$)$_2$ and O$CH_3$) and electron withdrawing groups (X =F and Cl), respectively. In the case of guest molecules containing electron donating groups, the fluorescence of macrocycle L was enhanced in the presence of the guest molecules. On the contrary, in the case of guest molecules containing electron withdrawing groups, it was almost quenched in the presence of those.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1429-1434
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• 2013

A synthesis and cation-induced fluorescent behavior of the carbazole-attached $NO_2S_2$-macrocycle (L) is described and structurally characterized by single crystal X-ray analysis. The photoluminescence spectrum of L in 80% $CH_3CN/CH_2Cl_2$ displays a peak maximum at 431 nm (blue emission). In the metal-induced fluorometric experiment, L showed a drastic chelation-enhanced fluorescence quenching (CHEQ) effect only with $Hg^{2+}$ and $Cu^{2+}$. In ESI-mass study, a 1:1 stoichiometry for complexation of L with $Hg^{2+}$ was confirmed, suggesting the unique sensing behavior of the proposed ligand L due to the selective complexation affinity for $Hg^{2+}$. The observed results indicate that L is a promising turn-off type fluoroionophore for $Hg^{2+}$ and $Cu^{2+}$ detections. Additionally, the $Ag^+$ complex of the precursor macrocycle was prepared and its solid structure was crystallographically characterized.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2031-2035
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• 2010

A triple-probe channel type chemosensor based on an $NO_2S_2$-macrocycle functionalized with phenyltricyanovinyl group was synthesized and its sensing characteristics were examined. The pink-red solution of L changed selectively to pale yellow upon addition of $Hg^{2+}$. The selective fluorometric response of L to all the tested metal ions was studied. The results showed that a large enhancement of the fluorescence of L was observed only in the case of $Hg^{2+}$. In addition, L showed large anodic shift (~ 0.3 V) for the addition of excess $Hg^{2+}$. Through above three observed results by the different techniques, we confirmed that the proposed chemosensor acts as the multiple-probe channel sensing material. The crystal structure of mercury(II) nitrate complexs of L which shows a 1-D polymer network with a formula $[Hg_2(L)_2(NO_3)_2({\mu}-NO_3)_2]_n$ was also reported.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3707-3710
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• 2010

A chromo/fluorogenic $NO_2S_2$-macrocycle L functionalized with nitrobenzofurazan unit as a dual-signaling probe was synthesized and structurally characterized by single crystal X-ray analysis. In a cation-induced color change experiment, L exhibited excellent $Hg^{2+}$ ion selectivity by showing the color change from orange-red to yellow. However, this hypochromic shift by $Hg^{2+}$ was observed for the weaker coordinating anion system such as ${NO_3}^-$ and ${ClO_4}^-$ ions. The observed anion effect is due to the strong coordination of anions inhibits the bond formation between $Hg^{2+}$ and the macrocyclic tert-N atom, which is sensitive to induce the color change. In the fluorometric experiment, L showed chelate-enhanced fluorescence change effect only with $Hg^{2+}$ ion, together with a change from yellow to green emission. The sensing ability for $Hg^{2+}$ with the proposed chemosensor L is due to the stable complexation with 1:1 stoichiometry (metal-to-ligand).

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2701-2704
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• 2010

This work shows that both L2 and L3 bearing two and four N-$(CH_2)_2OCH_3$ groups, respectively, can be prepared selectively by the reaction of $L^1$ with 1-bromo-2-methoxyethane. The di-N-substituted macrocycle $L^2$ readily forms its copper(II) and nickel(II) complexes. The N-$(CH_2)_2OCH_3$ groups in $[CuL^2]^{2+}$ are coordinated to the metal ion, whereas those in $[NiL^2]^{2+}$ are not involved in coordination. Interestingly, $L^3$ reacts with $Cu^{2+}$ ion to form $[Cu(HL^3)]^{3+}$, in which one tertiary amino group is not involved in coordination.

• Korean Journal of Crystallography
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• v.6 no.2
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• pp.80-87
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• 1995

The structure of Tetrapropionyloxycalix[4]arene(C40H40O8) has been studied by X-ray diffraction method. The crystal is monoclinic a=13.921(3), b=13.552(2), c=19.840(5)Å, β=110.38(2)°, Z=4 T=297K, Dc=1.23gcm-3, F(000)=1376, Systematic absences : hkl none, h0l : h+l=2n, 0k0: k=2n define space group P21/n. The structure was solved by direct method and refined by full-matrix least-squares methods to final R of 0.06 for 2514 observed reflections. The macrocycle exists in partial cone conformation. Three propionyl groups direct toward the exterior of the macrocycle cavity.

• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.81-85
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• 2002

A new di-N-cyanoethylated 14-membered tetraaza macrocycle 1,8-bis(2-cyanoethyl)-3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradecane $(L^2)$ and its nickel(II) complex $[NiL^2(OAc)]^+$ have been prepared. The square-planar complex $[NiL^2](C IO_4)_2$ can be prepared by addition of $HClO_4$ to a hot aqueous solution of $[NiL^2(OAc)]^+$ The Ni-N (tertiary amino group) bond distances $(2.008{\AA})$ of $[NiL^2](C IO_4)_2$ are relatively long, and the complex exhibits a d-d transition band at unusually long wavelength (ca. 515 nm). The complex $[NiL^2](C IO_4)_2$ rapidly reacts with acetate ion or ethylenediamine (en) to produce $[NiL^2(OAc)]^+$ or [Ni(en)_3]^{2+}$, respectively, and is readily decomposed in NaOH (0.01 M) solution. The chemical properties of $[NiL^2]^{2+}$ as well as its synthetic procedure are quite different from those for other related 14-membered tetraaza macrocyclic complexes. Effects of the N-cyanoethyl and C-methyl groups on the properties of $L^2$.

• Korean Journal of Crystallography
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• v.11 no.3
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• pp.147-150
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• 2000

The complex [CuL}Cl₂·3H₂O(1)(L=2,13-bis(2-hydroxyethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0/sup 1.18/,0/sup 7.12/] docosane) has been synthesized and characterized by X-ray crystallography. 1. crystallized in the monoclinic, space group C2/c, with a=21.647(6)Å, b=8.549(1)Å, c=18.132(5)Å, β=118.58(2)°, V=2946.8(12)ų, Z=4, R₁(wR₂) for 2374observed reflections of [I>2σ(I)] was 0.052(0.187). The centrosymmetric complex 1 has an axially elongated octahedral geometry with four secondary and tertially amines of the macrocycle and tow oxygen atoms of the pendant hydroxyethyl groups.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1150-1154
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• 2003

The reactions of [Ni(L)(H₂O)₂]Cl₂ (L = 2,5,9,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane) with terephtalate (tp) and 2,5-pyridinedicarboxylate (pdc) generate one-dimensional nickel(II) complexes, [Ni(L)(H₂O)₂](tp) · ₄H₂O (1) and [Ni(L)(H₂O)₂](pdc)·₄H₂O (2). The structures have been characterized by X-ray crystallography, magnetic susceptibility and spectroscopy. The crystal structures of 1 and 2 show a distorted octahedral coordination geometry around the Ni(II) ion, with secondary amines of the macrocycle and two water molecules at the trans position. Complexes 1 and 2 display the one-dimensional hydrogen-bonded infinite chains. The magnetic behavior of all compounds exhibits weak interchain antiferromagnetic interactions with J values of -1.09(3) for 1 and -1.14(2) cm-1 for 2.