Designer SMM: An ErIII-based single-molecule magnet (SMM) was synthesized by designing the ligand-field anisotropy around an ErIII ion in equatorial arrangement of donors using a rigid and planar macrocyclic Schiff base ligand including three ZnII ions. The resulting ErIIIZnII3 complex (see picture; C gray, O red, N blue) behaves as SMM with energy barrier 24.6(9) K for flipping molecular magnetic moment. Detailed facts importance to specialist readers are published "Supporting Information"....

Although salen and its analogues are versatile chelate ligands in inorganic organometallic chemistry, synthesis of unsymmetrical derivatives consisting two different salicylideneimine moieties is difficult because the CN bond recombination. To develop stable salen-type ligands, we synthesized a series new salamo (=1,2-bis(salicylideneaminooxy)ethane) on basis O-alkyl oxime instead imine moiety. Eight 1a−h were prepared 64−88% yields as colorless crystals from corresponding salicylaldehydes...

This review describes the design and synthesis of hosts based on salen or related N(2)O(2) ligands, which are useful for development cooperative metal complexation systems. A key to N(2)O(2)-based metallohosts is negative charges phenoxo groups, further coordinate ions in a bridging fashion. In particular, integration two more coordination sites effective construction metallohosts. variety cyclic acyclic oligo(N(2)O(2)) compounds were designed synthesized. They show unique behavior due...

We have designed a new type of bis(N2O2) chelate ligand that affords C-shaped O6 site on the metalation N2O2 sites. UV-vis and 1H NMR titration clearly showed complexation between H4L zinc(II) acetate 1:3 complex [LZn3]2+ via highly cooperative process. Although O6-recognition dinuclear metallohost [LZn2] is filled with additional Zn2+, can bind guest ion concomitant release initially bound Zn2+. The novel recognition process "guest exchange" took place quantitatively when rare earth metals...

We have synthesized an octanuclear zinc(II) cluster [L4Zn8(H2O)3] by the complexation of 3-hydroxysalamo (H4L) with acetate. The complex crystallizes in triclinic system, space group P, unit cell parameters a = 18.233(10) A, b 20.518(11) c 21.366(11) alpha 98.7557(2) degrees, beta 99.191(11) gamma 108.309(10) and Z 4. crystallographic analysis revealed S4 symmetrical assembling four ligands that tetrameric has three water molecules unsymmetrical fashion. Spectroscopic strongly suggests also...

Development of artificial helical molecules that can undergo responsive helicity inversion has been a challenging research target in functional molecular chemistry. However, most reported inversions are based on single-mode transition, i.e., the conversion between right- and left-handed states. We report here first system allows stepwise multisequential utilizing metal exchange complexes derived from hexaoxime ligand, H6L1. The ligand H6L1 underwent four-step (H6L1 → L1Zn3 L1Zn5 L1Zn3Ba...

The helical tetranuclear complex [LZn(3)La(OAc)(3)] having two benzocrown moieties was designed and synthesized as a novel molecular leverage for helicity control helix inversion. Short alkanediammonium guests H(3)N(+)(CH(2))(n)NH(3)(+) (n = 4, 6, 8) preferentially stabilized the P-helical isomer of [LZn(3)La(OAc)(3)], while longer guest H(3)N(+)(CH(2))(12)NH(3)(+) caused inversion to give M-helical major isomer. differences in lengths were efficiently translated into handedness via...

A macrocyclic bisBODIPY (bis(boron-dipyrromethene)) complex [1B2] with a figure-of-eight helicity was synthesized and successfully resolved. proven to be one of the most efficient red-emitting CPL (circularly polarized luminescence) fluorophores reported date (λ = 663 nm, |glum| 9 × 10(-3), ΦF 0.58).

Abstract Novel ligands 1,2-bis(salicylideneaminooxy)ethanes were synthesized. They much more stable against exchange reactions of aldehyde units than the corresponding salen derivatives. form complexes with a copper(II) ion, whose structures crystallographically determined. Spectroscopic and electrochemical studies indicated that have lower LUMO levels analogues.

Only the central metal atom of homotrinuclear complex [LZn3]2+, prepared by cooperative complexation between a linear ligand and Zn(OAc)2, is replaced with Ln3+ ion selective quantitative transmetalation to give helical heterotrinuclear [LZn2Ln]3+ (see scheme). Ln=lanthanide. Supporting information for this article available on WWW under http://www.wiley-vch.de/contents/jc_2002/2002/z19528_s.pdf or from author. Please note: The publisher not responsible content functionality any supporting...

Ca2+-selective recognition was achieved by using the site-selective transmetalation of homotrinuclear metallohost [L1Zn3]2+ containing a linear tetraoxime ligand. The selectivity (log(KCa/KMg) > 5.1) is comparable to those excellent Ca2+ receptors or sensors such as BAPTA, Quin2, and K23E1. X-ray crystallography revealed that complex [L1Zn2Ca]2+ has helical structure. On other hand, larger analogue H6L2 gave mixture [L2Zn4]2+ isomers, which selectively recognizes Ba2+ give single...

The aluminium complexes of N(2)O(2)-dipyrrins were synthesized and the absorption/fluorescence spectral changes caused by complex formation with ZnCl(2), ZnBr(2) Zn(OAc)(2) examined.

A C3-symmetric chiral concave molecule having a phosphorus atom at the center was synthesized, and its enantiomers were resolved. The shape absolute structure of molecules revealed by X-ray analysis. exhibited intense chiroptical properties with large anisotropy, which derived from molecular orbitals delocalized to side chains. In co-crystal pristine C60, four enantiopure perfectly wrapped surface C60. MALDI-TOF mass, NMR, circular dichromism spectra also supported concave/convex interaction...

Color-tunable resonant photoluminescence (PL) was attained from polystyrene microspheres doped with a single polymorphic fluorescent dye, boron-dipyrrin (BODIPY) 1. The color of the PL depends on assembling morphology 1 in microspheres, which can be selectively controlled green to red by initial concentration preparation process microspheres. Studies intersphere propagation multicoupled prepared micromanipulation technique, revealed that multistep photon transfer takes place through...

We designed a novel tricobalt(III) metallo-molecular cage in which its apertures can be closed with bifunctional ligands via coordination bonds. A closed-cage complex was easily formed by ligand exchange of open-cage analogue. Guest uptake/release the sufficiently fast to quickly reach guest-binding equilibrium, while that extremely slow and took about 1 week equilibrium. The guest uptake retarded at least 2000 times introduction apertures.

Novel trinuclear zinc(II) complexes [Zn3L2(OAc)2] (L = salamo, 3-MeOsalamo) were synthesized, and their structures determined by X-ray crystallography. Ligation of methoxy groups in the salamo ligand causes a significantly different coordination mode central zinc atom system. The between ligands methanol formed exclusively very cooperatively. In contrast to other imine ligands, mononuclear [ZnL] are not observed at all.

We have designed and synthesized a new Cu2Gd heterotrinuclear complex, [LCu2Gd(OAc)3] (1), where H4L is bis(salen)-type tetraoxime ligand useful in the synthesis of discrete (3d)2(4f) complexes. Complex 1 crystallizes triclinic system, space group P1, with unit cell parameters = 12.442(4) A, b 13.397(3) c 13.966(4) alpha 77.052(8) degrees, beta 88.656(10) gamma 77.761(8) Z 2. In crystal structure 1, Cu-Gd distances are 3.3-3.5 whereas two Cu atoms separated by 6.08 A. The corresponding...

Synthesis and binding behavior of a novel multi-responsive host 1, in which two esters, polyether moieties, urea sites, bipyridine units as ion sites are arranged on the calix[4]arene skeleton, is reported. 1 recognizes Na(+) Ag(+) simultaneously quantitatively captures an anionic guest. The ability to recognize anions, including CF(3)SO(3)(-) BF(4)(-), remarkably increases stepwise manner using effectors. enhancement K(a) eventually reaches factors 1500 2000 for NO(3)(-) CF(3)SO(3)(-),...

In supramolecular chemistry, a great deal of attention has focused on regulating guest binding via an external stimulus. To utilize the same effector for both highly guest-selective positive and negative allosteric effects, however, stricter more precise regulation host structure is required. A novel 1 binds Fe(II) to afford pseudocryptand, 1·Fe(II), which bears cavity that surrounded by three polyether chains in helical fashion. The selectivity (Na+ > K+ Rb+ Cs+) opposite 1·Fe(II) (Cs+...

A 36-membered macrocyclic hexaoxime was quantitatively obtained by [3 + 3] condensation of dialdehyde 2 with diamine 3 using La3+ (core metal) and Zn2+ (shell as a novel core/shell template, while the yield very low in absence metal ions. The high can be attributed to efficient formation 3:3:1 complex 2, Zn2+, La3+, which readily gives macrocycle keeping Zn3La tetranuclear cluster structure.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCharacterization of regiospecific AC- and AD-disulfonate capping .beta.-cyclodextrin. Capping as an efficient production techniqueIwao Tabushi, Kazuo Yamamura, Tatsuya NabeshimaCite this: J. Am. Chem. Soc. 1984, 106, 18, 5267–5270Publication Date (Print):September 1, 1984Publication History Published online1 May 2002Published inissue 1 September 1984https://doi.org/10.1021/ja00330a039Request reuse permissionsArticle...

We designed and synthesized a series of new α-bridged linear BODIPY oligomers, which exhibited strong absorption high fluorescence efficiency in the near infrared region. The oligomers can be reversibly converted to first NIR emissive foldamers upon selective complexation with Cs+.