Rare earth elements activate endocytosis in plant cells.

It has long been observed that rare earth elements (REEs) regulate multiple facets of plant growth and development. However, the underlying mechanisms remain largely unclear. Here, using electron microscopic autoradiography, we show the life cycle of a light REE (lanthanum) and a heavy REE (terbium) in horseradish leaf cells. Our data indicate that REEs were first anchored on the plasma membrane in the form of nanoscale particles, and then entered the cells by endocytosis. Consistently, REEs activated endocytosis in plant cells, which may be the cellular basis of REE actions in plants. Moreover, we discovered that a portion of REEs was successively released into the cytoplasm, self-assembled to form nanoscale clusters, and finally deposited in horseradish leaf cells. Taken together, our data reveal the life cycle of REEs and their cellular behaviors in plant cells, which shed light on the cellular mechanisms of REE actions in living organisms.

Copper-catalyzed regio- and stereoselective O-arylation of enolates.

Copper-catalyzed O-arylation of enolates with diaryliodonium salts as arylating reagents was realized successfully. As important building blocks, ß-aryloxy carbonyl compounds were obtained in up to 98% yield under mild conditions, and complete control of O-arylation and Z-stereoselectivity were achieved. The origin of the selectivity was also discussed.

Copper-catalyzed regioselective reaction of internal alkynes and diaryliodonium salts.

The copper-catalyzed highly regioselective reaction of internal alkynes with diaryliodonium salts was achieved for the first time. α-Arylketones were obtained in moderate to good yields from arylpropargylic alcohols or aryl alkyl alkynes under mild conditions. It was found that the two kinds of substrates underwent two different arylation-oxygenation pathways under different reaction conditions based on deuterated experiments, controlling experiments, and spectroscopic analysis of reaction intermediates.

Novel syntheses and properties of meso-tetraaryl-octabromo-tetranaphtho[2,3]porphyrins (Ar4Br8TNPs).

o-Quinodimethane (o-QDM) generated from benzosultine was used to extend the pyrrole system for the preparation of octabromo-tetranaphtho[2,3]porphyrins via oxidative aromatization. The properties of these bromoporphyrins were presented and chemical transformation via Pd-catalyzed Suzuki reaction was also effectively achieved.

The silica-like extended polymorphism of cobalt(II) imidazolate three-dimensional frameworks: X-ray single-crystal structures and magnetic properties.

Five polymorphous frameworks of cobalt(II) imidazolates (1-5) have been prepared by solvatothermal syntheses. Of these, compound 3 has already been synthesized in a gas-phase reaction by Seel et al. in 1969 and structurally characterized by Sturm et al. in 1975. The new synthetic strategy affords four polymorphous frameworks of cobalt(II) imidazolates (1, 2, 4, 5) of crystalline substances, of which the compound 4 (a = b = 23.450(3), c = 12.460(3) A, tetragonal, I4(1)cd, Z = 16) is an isomorphous compound of [Zn(im)(2)]( infinity ), which was also synthesized in a gas-phase reaction in 1980. The frameworks of compounds 1 and 2 are porous and isostructural; they have the same framework topology that represents a novel uninodal (6,4)-net: 1: a = 18.513(4), b = 24.368(5), c = 9.2940(19) A, orthorhombic, Fdd2, Z = 16; 2: a = 17.635(4), b = 27.706(6), c = 9.0810(18) A, orthorhombic, Fdd2, Z = 16. The framework of compound 5 exhibits a topology of zeolitic structure with the unit-cell parameters: a = 24.3406(8), b = 9.4526(3), c = 24.8470(8) A, beta = 91.977(1) degrees, monoclinic, P2(1)/n, Z = 4. All polymorphous frameworks of cobalt(II) imidazolates reflect the structural features of silica (SiO(2)) and also exhibit different magnetic behaviors, although the imidazolates transmit the antiferromagnetic coupling between the cobalt(II) ions in all cases. However, the uncompensated antiferromagnetic couplings arise from spin-canting are sensitive to the structures: compound 1 is an antiferromagnet with T(N) = 13.11 K; compounds 2-4 are weak ferromagnets (canted antiferromagnets): 2 shows a very weak ferromagnetism below 15 K, 3 exhibits a relatively strong ferromagnetism below 11.5 K and a coercive field (H(C)) of 1800 Oe at 1.8 K, and 4 displays the strongest ferromagnetism of the three cobalt imidazolates and demonstrates a T(C) of 15.5 K with a coercive field, H(C), of 7300 Oe at 1.8 K. However, compound 5 seems to be a hidden canted antiferromagnet with a magnetic ordering temperature of 10.6 K.

The mononuclear cobalt(II) complex CoII(DMBDIZ)2(NCS)2, where DMBDIZ is 2,6-dimethylbenzo[1,2-d:4,5-d']diimidazole.

In the title mononuclear cobalt complex, bis(2,6-dimethyl-1H,7H-benzo[1,2-d:4,5-d']diimidazole-kappaN(3))bis(thiocyanato-kappaN)cobalt(II), [Co(II)(NCS)(2)(DMBDIZ)(2)] or [Co(NCS)(2)(C(10)H(10)N(4))(2)], the cobalt(II) ion is coordinated to four N atoms, from two thiocyanate anions and two DMBDIZ ligands, in a distorted tetrahedral geometry. In the DMBDIZ ligand, the two imine N atoms are positioned cis with respect to one another. The crystal packing of the complex is dominated by both hydrogen bonding, involving two N-H...N and two N-H...S interactions, and aromatic pi-pi stacking.