Fmoc-D-MePhe(4-F)-OH

Based on the anion template and chiral ligand inducting role, two series of high-nuclearity 3 d-4 f heterometallic clusters with formulas [NO3@Ln6Cu24(μ3-OH)30(μ2-OH)3(OAc)6( R/ S-L)12(H2O)24](NO3)14· x(H2O) (Ln = Dy, x = 30 for 1a( R-L) and 1b( S-L); Ln = Tb, x = 40 for 2a( R-L) and 2b( S-L)) and (Et3NH)4[Ln6Cu12(μ3-OH)14(μ2-Cl)6Cl12( R/ S-L)12]Cl2· x(H2O) (Ln = Dy, x = 28 for 3a( R-L) and 3b( S-L); Ln = Tb, x = 33 for 4a ( R-L) and 4b( S-L); HL = ( R/ S)-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid), have been synthesized and characterized. Structural analysis reveals that the metal skeleton of compounds 1 and 2 display a Ln6Cu12 octahedral inner core encapsulated by six outer Cu2 units. In the Ln6Cu12 octahedron, 6 Ln3+ ions located at the six vertices and 12 inner Cu2+ ions located at the 12 edges of octahedron, and one NO3- locates in the center of the octahedron. The metal core of compounds 3 and 4 can be viewed as a Ln6 octahedron encapsulated by six Cu2 units. It is interesting that the different inorganic anions involved in the reaction result in the difference in the structures of 1 to 2 and 3 to 4. Circular dichroism spectra of 1-4 display obvious mirror symmetry effect at 600-800 nm of d-d transition of Cu2+, suggesting that the chirality transferred from chiral R- and S-ligand to Cu2+ ions in this system. Notably, the CD peak at the Cu2+ d-d transition position of Ln6Cu12 cluster is obviously blue-shifted compared with that of Ln6Cu24 due to the different coordinated environments of Cu2+. Magnetic studies indicate that 1a and 2a show weak ferromagnetic interactions, while 3a and 4a display antiferromagnetic interactions.

Phenylboronic acids (PBAs) are an important class of compounds with diverse applications in synthetic, biological, medicinal, and materials chemistry. In this investigation we report structural and thermochemical parameters for several monosubstituted ortho, meta, and para PBAs, R-B(OH)2 (R = C6H5, C6H4CH3, C6H4NH2, C6H4OH, and C6H4F). Equilibrium geometries of all the PBAs discussed in this article were obtained using second-order Møller-Plesset perturbation theory (MP2) with the Dunning-Woon aug-cc-pVDZ basis set; heats of formation (HOF) were calculated at the Gaussian-3 (G3) level of theory. The endo-exo conformers of all the positional isomers of these PBAs were lowest in energy. Using HOF for the monosubstituted PBAs calculated at the G3 level of theory, in conjunction with the experimental HOF for benzene, toluene, aniline, phenol, and fluorobenzene, the values of [Formula: see text] for the transfer processes C6H6 + C6H4X-B(OH)2 → C6H5X + C6H5-B(OH)2 (X = CH3, NH2, OH, and F) are found to be in good agreement with values of [Formula: see text] calculated at the MP2(FC)/aug-cc-pVTZ//MP2(FC)/aug-cc-pVTZ computational level; the bonding in the reactants and products for these transfer reactions are well-matched and thermochemical calculations at this level are expected to be very accurate, providing checks on the G3 HOF calculations.

A new sodium hydroxyfluorooxoborate, NaB3O4F(OH) (NBOFH), was discovered and synthesized. NBOFH features the unprecedented [B3O4F(OH)] infinite chain constructed by the novel fundamental building block (FBB) of [B3O5F(OH)]. NBOFH has a large birefringence of 0.097 at 1064 nm and short ultraviolet (UV) cutoff edge below 200 nm. First-principles calculations and response electron distribution anisotropy (REDA) were performed to explain the structure-property relationships. This work provides a novel strategy for the synthesis of deep-ultraviolet birefringent crystals and enriches the structural diversity of the emerging hydroxyfluorooxoborates.