The reactions of a racemic four-coordinated nickel(II) complex [Ni(alpha-rac-L)](ClO4)2 (containing equal amount of SS and RR enantiomers) with l- and d-phenylalanine in acetonitrile/water gave two less-soluble six-coordinated enantiomers of {[Ni( f-SS-L)(l-Phe)](ClO4)}n (Delta-1) and {[Ni(f- RR-L)(d-Phe)](ClO4)}n (Lambda-1), respectively. Evaporation the remaining solutions gave two six-coordinated diastereomers of {[Ni 3(f- RR-L)3(l-Phe)2(H 2O)](ClO4)4}n (a-2) and {[Ni3(f- SS-L)3(d-Phe)2(H2O)](ClO4)4}n (b-2), respectively (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, Phe(-) = phenylalanine anion). The reaction of [Ni(alpha-rac-L)](ClO4)2 with dl-Phe(-) gave a conglomerate of c-1; in which, the SS and RR enantiomers preferentially coordinate to l- and d-Phe(-) respectively to give a racemic mixture of Delta-1 and Lambda-1, and the spontaneous resolution occurs during the reaction, in which each crystal crystallizes to become enantiopure. Removing Phe(-) from Delta-1 and Lambda-1 using perchloric acid gave two enantiomers of [Ni(alpha-SS-L)](ClO4)2 (S-3) and [Ni(alpha-RR-L)](ClO4)2 (R-3). Dissolving S-3 and R-3 in acetonitrile gave two six-coordinated enantiomers of [Ni( f-SS-L)(CH3CN)2](ClO4)2 (S-4) and [Ni( f- RR-L)(CH3CN)2](ClO4)2 (R-4), while dissolving [Ni(alpha-rac-L)](ClO4)2 in acetonitrile gave a racemic twining complex [Ni(f-rac-L)(CH3CN)2](ClO4)2 (rac-4). Delta-1 and Lambda-1 belong to supramolecular stereoisomers, which are constructed via hydrogen bond linking of [Ni( f-SS-L)(l-Phe)](+) and [Ni(f-RR-L)(d-Phe)](+) monomers to form 1D homochiral right-handed and left-handed helical chains, respectively. The reaction of S-3 with d-Phe(-) gave {[Ni(f-SS-L)(d-Phe)](ClO4)}n (5), which shows a motif of a 1D hydrogen bonded zigzag chain instead of a 1D helical chain. Compound a-2/ b-2 contains dimers of [{Ni(f-RR-L)}2(l-Phe)(H2O)](3+)/[{Ni( f- SS-L)}2(d-Phe)(H2O)](3+) and 1D zigzag chains of {[Ni(f-RR-L)(l-Phe)](+)}n /{[Ni(f-SS-L)(d-Phe)](+) n . The homochiral nature of Delta-1/Lambda-1, a-2/b-2, S-3/R-3, and S-4/R-4 are confirmed by the results of circular dichroism (CD) spectra measurements.

The reactions of four-coordinated transition metal macrocyclic complexes [ML](ClO(4))(2) (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, M = Ni, Cu) with NH4VO3 under different conditions gave four coordination polymers of {[(CuL)(0.5)(H2L)(1.5)][H2V10O2)] x 6H(2)O}(n) (1x6H(2)O), {[NiL](3)[V16O38(H2O)] x 6H(2)O}(n) (2 x 6H(2)O), {[NiL][VO(3)](2) x 0.33H2O}(n) (3.0.33H(2)O), and {[CuL][VO(3)](2) x 0.33H(2)O}(n) (4 x 0.33H2O). Single crystal X-ray diffraction analyses reveal that four diverse vanadium polyoxoanions, [H2V1oO28)(4-) cluster, [V16O38(H2O)](6-) cage, [V6O18](6-) ring, and [VO(3)](n)(n-) chain, were obtained from the same reactant NH(4)VO(3) under different conditions. In 1, the cluster anion [H2V10O28](4-) alternately bridges [CuL]2+/[H2L]2+ to form a one-dimensional chain, and the [V16O38(H2O)](6-) cage in 2 links three [NiL]2+ into a two-dimensional sheet. Compounds 3 and 4 show three-dimensional structures, which are constructed by the connections of hexanuclear [V6O18](6-) rings with [NiL]2+ in 3 and [VO3](n)(n-) chains with [CuL]2+ in 4, respectively, generating one-dimensional channels occupied by guest water molecules.

We first report the direct ortho C–H amidation of arenes with azides by using a novel and inexpensive RuHCl­(CO)­(PPh3)3 catalyst. The reaction proceeds efficiently in high yield over a broad range of substrates without requirement of any additional silver salt or additive.

A novel pyromellitic diimide-extended pillar[6]­arene was synthesized in two steps with moderate yield for the first time. It showed a symmetrical stretched hexagon structure and could form 1:2 complexes with polycyclic aromatic hydrocarbons in solution. Interestingly, a linear supramolecular array between complex 1@G4 2 and pyrene through π···π stacking interactions was also observed in the solid state.

Through a combinatorial screening of 35 possible phase-selective monopeptide-based organogelators readily made at low cost, we identified five of them with high gelling ability toward aprotic aromatic solvents in the powder form. The best of them (Fmoc-V-6) is able to instantly and phase-selectively gel benzene, toluene, and xylenes in the presence of water at room temperature at a gelator loading of 6% w/v. This enables the gelled aromatics to be separated by filtration and both aromatics and the gelling material to be recycled by distillation. We also identified Fmoc-I-16 as the best gelator for benzyl alcohol, and the corresponding organogel efficiently removes toxic dye molecules by 82−99% from their highly concentrated aqueous solutions. These efficient removals of toxic organic solvents and dyes from water suggest their promising applications in remediating contaminated water resources.

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The highly diastereoselective intramolecular [3+2] annulation via the ring-opening of a cyclopropane diester derivative has been developed to construct a dihydroquinolinone scaffold. A series of tricyclic dihydroquinolinones bearing one or two all-carbon quaternary stereogenic centers were obtained in good yields and excellent diastereoselectivities (up to 20 : 1 dr). Moreover, the amide-linking mode shows obviously beneficial effects on the ring-opening of cyclopropane.

The enantiopure agents d- and l-leucine, selectively bind RR and SS enantiomers from a racemate [Ni(alpha-rac-L)](2+) to give {[Ni(RR-L)(d-HLeu)](ClO(4))(2)}(n) (Delta-) and {[Ni(SS-L)(l-HLeu)](ClO(4))(2)}(n) (Lambda-), respectively, and leave the corresponding uninteracted SS and RR enantiomers of [Ni(alpha-SS-L)](ClO(4))(2) (S-) and [Ni(alpha-RR-L)](ClO(4))(2) (R-). Occasionally, a few crystals of {[Ni(RR-L)(l-HLeu)](ClO(4))(2)}(n) (Delta-) and {[Ni(SS-L)(d-HLeu)](ClO(4))(2)}(n) (Lambda-) were found to have accreted with the crystals of Lambda-/R-, and Delta-/S-, respectively (the yields are less than 2%). The results of X-ray crystal structural analysis reveal that Delta- and Lambda-, S- and R-, and Delta- and Lambda- are enantiomers, in which Delta- and Delta- possess 1D right-handed helical chains, while Lambda- and Lambda- exhibit a motif of 1D left-handed helical chains. The results of DFT calculations reveal that the single-point energies of [Ni(RR-L)(d-HLeu)](2+)/[Ni(SS-L)(l-HLeu)](2+) in Delta-/Lambda- are 582 kJ mol(-1) lower than those of [Ni(RR-L)(l-HLeu)](2+)/[Ni(SS-L)(d-HLeu)](2+) in Delta-/Lambda-, demonstrating the favorable stereo-coordination environments of [Ni(alpha-RR-L)](2+) and [Ni(alpha-SS-L)](2+) towards d and l-HLeu, respectively.