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A synthesis of the benzothiazepine phosphonic acid 3, employing both enzymatic and transition metal catalysis, is described. The quaternary chiral center of 3 was obtained by resolution of ethyl (2-ethyl)norleucinate (4) with porcine liver esterase (PLE) immobilized on Sepabeads. The resulting (R)-amino acid (5) was converted in two steps to aminosulfate 7, which was used for construction of the benzothiazepine ring. Benzophenone 15, prepared in four steps from trimethylhydroquinone 11, enabled sequential incorporation of phosphorus (Arbuzov chemistry) and sulfur (Pd(0)-catalyzed thiol coupling) leading to mercaptan intermediate 18. S-Alkylation of 18 with aminosulfate 7 followed by cyclodehydration afforded dihydrobenzothiazepine 20. Iridium-catalyzed asymmetric hydrogenation of 20 with the complex of [Ir(COD)2BArF] (26) and Taniaphos ligand P afforded the (3R,5R)-tetrahydrobenzothiazepine 30 following flash chromatography. Oxidation of 30 to sulfone 31 and phosphonate hydrolysis completed the synthesis of 3 in 12 steps and 13% overall yield.

Ba3FeUS6 (I) and Ba3AgUS6 (II) are prepared by reactions of BaS, U, S, M (Fe or Ag), and Sb2S3 as flux (evacuated silica tubes, 1223 K, 8 d).

The title compound is synthesized ba solid state reaction of an equimolar mixture of the elements (evacuated silica tube, 1273 K, 99 h) followed by treatment in a Sb2Se3 flux under the same conditions.

In the presence of Ti(OiPr)4, NHC and TAB, enals like (I) undergo dimerization with high diastereo- and enantioselectivity yielding cyclopentenes of type (III).

The role of charge density matching in the formation of templated molybdates under mild hydrothermal conditions was investigated through the use of a series of structurally related amines: piperazine, 1,4-dimethylpiperazine, 2,5-dimethylpiperazine and 2,6-dimethylpiperazine. A series of reactions was conducted in which the relative mole fractions of each component were fixed at 2.5 MoO3:1 amine:330 H2O:2 H2SO4 in order to isolate the effects of the amine, the only variation between reactions was the structure of the amine. Four distinct polyoxomolybdates anions were observed, ranging from zero-dimensional β-[Mo8O26]4− molecular anions to [Mo3O10]n2n− and [Mo8O26]n4n− chains and [Mo5O16]n2n− layers. The primary influence over the structure of the molybdate anion is charge density matching with the protonated amine, which was quantified through surface area approximations based upon both calculated molecular surfaces and polyhedral representations of each anion. Secondary influences include amine symmetry and hydrogen-bonding preferences. The synthesis and characterization of two new compounds are reported. Crystal data: [C6H16N2][Mo3O10]·H2O (1), triclinic, P-1 (no. 2), a=8.0973(7) A, b=8.8819(9) A, c=11.5969(11) A, α=71.362(9)°, β=82.586(8)°, γ=74.213(8)°, Z=2, R/Rw=0.0262/0.0564, and [C6H16N2]2[Mo8O26] (2), monoclinic, P21/n (no. 14), a=7.9987(11) A, b=12.5324(19) A, c=16.003(3) A, β=97.393(14)°, Z=2, R/Rw=0.0189/0.0454.

Single crystals of a new β-octamolybdate salt containing protonated 1,4-diazabicyclo[2.2.2]octane cations were prepared under mild hydrothermal conditions. This compound, [C6H13N2]2[C6H14N2][Mo8O26], was then used as a starting material in the synthesis of [C6H13N2]6[Mo16O53F2]·4H2O, which contains previously unreported [Mo16O53F2]12- anions. The structure-directing properties of γ-[Mo8O26]4-, a likely intermediate in this pH-dependent transformation, are responsible for the site selection of the fluoride incorporation. [Mo16O53F2]12-, the largest reported polyoxofluoromolybdate cluster, expands upon the limited number of such anions in the literature. The structures of both compounds were determined using single-crystal X-ray diffraction.

Recent work in the preparation of organically templated metal sulfates under hydrothermal conditions has been extended to include the sulfation of α-molybdena through the synthesis of [C5H14N2][(MoO3)3(SO4)]·H2O. Single crystals were grown under hydrothermal conditions from molybdenum oxide, water, sulfuric acid, and an enantiomerically pure (R)-2-methylpiperazine source and characterized using both single-crystal X-ray diffraction and infrared spectroscopy. One-dimensional [(MoO3)3(SO4)]n2n- chains, based on a neutral α-molybdena backbone, are connected through an extensive hydrogen-bonding network containing [C5H14N2]2+ cations and occluded water molecules. The direction of the hydrogen bonding is primarily dictated by the nucleophilicity of the respective oxide ligands, as determined using bond valence sums.