Volume 77, Issue 7-8

The electron density distribution (EDD) of a tetrasaccharide composed of four benzoylated fructopyranosyl units was obtained by refinement with scattering factors from the invariom library. X-ray diffraction data was downloaded from the Cambridge Structural Database (CSD). Bond topological and atomic properties were obtained by application of Bader’s QTAIM formalism. From a large number of 105 C–C bonds in the molecule average bond orders for 33 single and 72 aromatic bonds were calculated yielding values of 1.33 and 1.61. Molecular Hirshfeld and electrostatic potential (ESP) surfaces show that only weak non-covalent interactions exist. The phenyl rings of the benzoyl fragments in the outer regions of the molecule generate a positive ESP shell with repulsive properties between adjacent molecules. Weak surface interactions result in a rather unusual low density around 1.3 g cm −3 , which is understandable when compared to other carbohydrates where strong O–H⋯O hydrogen bonds allow a 20% more dense packing with densities >1.5 g cm −3 as determined by single crystal X-ray diffraction.

All representatives of the isotypic series Ln Sb 2 O 4 Cl ( Ln  = Gd–Lu) could be obtained as single crystals, which crystallize just like the prototypic YSb 2 O 4 Cl in the non-centrosymmetric tetragonal space group P 42 1 2. The steady decrease in lattice parameters from a  = 781.08(4) pm and c  = 881.47(6) pm for GdSb 2 O 4 Cl to a  = 764.66(4) pm and c  = 877.53(7) pm for LuSb 2 O 4 Cl reflect the consequences of the lanthanide contraction, as expected. The Ln 3+ cations reside in the surrounding of eight oxygen atoms arranged as square hemiprisms [ Ln O 8 ] 13− , which are linked by four of their coplanar edges to form layers according to 2 ∞ { [ L n O 8 / 2 e ] 5 − } $\begin{array}{l}2\hfill \\ \infty \hfill \end{array}\left\{{\left[Ln{\text{O}}_{8/2}^{e}\right]}^{5-}\right\}$ parallel to the (001) plane. The Sb 3+ cations form ψ 1 -tetrahedral [SbO 3 ] 3– anions together with three oxygen atoms. Two of these anions are connected with additional Sb 3+ cations, but the third one shows no extra connectivity. Four ψ 1 -tetrahedral [SbO 3 ] 3– units build an eight-membered ring 0 ∞ { [ Sb 4 O 8 ] 4 − } $\begin{array}{l}0\hfill \\ \infty \hfill \end{array}\left\{{\left[{\text{Sb}}_{4}{\text{O}}_{8}\right]}^{4-}\right\}$ . These isolated rings are arranged parallel to the (001) plane. Between the oxygen-connected triple layers of Ln 3+ and Sb 3+ cations with the composition 2 ∞ { [ L n Sb 2 O 4 ] + } $\begin{array}{l}2\hfill \\ \infty \hfill \end{array}\left\{{\left[Ln{\text{Sb}}_{2}{\text{O}}_{4}\right]}^{+}\right\}$ there are single layers of Cl − anions, not connected strongly to any of the trications. Due to the presence of isolated cyclic [Sb 4 O 8 ] 4– anions, these lanthanoid(III) oxidoantimonate(III) chlorides Ln Sb 2 O 4 Cl ( Z  = 4) can also be described with the molecular formula Ln 2 [Sb 4 O 8 ]Cl 2 ( Ln  = Gd–Lu) for Z  = 2.

Iminium-functionalized 2,3-dihydroisoxazoles (4-isoxazolines) were prepared in high yields by [3+2] cycloaddition of N -methyl- C -phenylnitrone and acetylenic iminium salts. Conversion of the very hygroscopic cycloadducts into neutral compounds was achieved by hydrolysis or hydride reduction of the iminium functional group. By a thermal rearrangement, the cycloadducts were converted into 2,3-dihydro-1 H -imidazolium salts. With C , N -diphenylnitrone as the reaction partner, the expected cycloadduct, a [(2,3-dihydroisoxazol-4-yl)-1-(phenyl)methylene]- N , N -dimethylammonium triflate, could be prepared at −75°C and was characterized by NMR. This product was found to be thermally unstable above −30°C, being converted into an inseparable product mixture. Basic hydrolysis of this mixture afforded a structurally interesting acyclic enaminone/half-aminal, which is likely derived from a 2,3-dihydro-1,3-oxazole.

4-CF 3 -pyrido[1,2- a ]pyrimidin-5-ium triflates could be prepared in fair to high yields from acetylenic iminium salts R-C≡C–C(CF 3 )=N + Me 2 ·CF 3 SO 3 − and 2-aminopyridinium triflate under thermal conditions. Their reactions with protic heteronucleophiles, leading to 4-CF 3 , 4-XR-substituted 1,4-dihydropyrido[1,2- a ]pyrimidin-5-ium salts, have been studied and reversible addition as well as subsequent opening of the pyrimidine ring have been observed. The cyclocondensation of a 3-phenyl-propyniminium triflate and 3-aminoyridinium triflate required strong thermal activation and yielded a 4-CF 3 -and a 4-CF 3 ,5-CH 3 -[1,7]naphthyridine. A 1-CF 3 -benzo[ f ][1,7]naphthyridine was obtained from the same propyniminium salt and 3-aminoquinolinium triflate.

Low temperature reactions of 1,4-dichloro-2,5-dimethoxybenzene with two equivalents of lithium diisopropylamide (LDA) followed by quenches with chlorophosphines ClPR 2 ( R  = Ph or i Pr) yielded 1,4-bis(diphenylphosphino)-2,5-dichloro-3,6-dimethoxy-benzene ( 1a ) and 1,4-bis(diisopropylphosphino)-2,5-dichloro-3,6-dimethoxy-benzene ( 1b ). Reactions of 1a-b with 30% hydrogen peroxide yielded 1,4-bis(diphenylphosphinyl)-2,5-dichloro-3,6-dimethoxybenzene ( 2a ) and 1,4-bis(diisopropylphosphinyl)-2,5-dichloro-3,6-dimethoxybenzene ( 2b ). Subjecting compounds 2a-b to BBr 3 /CH 3 OH resulted in 2,5-bis(diphenylphosphinyl)-3,6-dichlorohydroquinone 3a and 2,5-bis(diisopropylphosphinyl)-3,6-dichlorohydroquinone 3b . Reactions of 3a-b with K 2 S 2 O 8 under basic conditions followed by acidification allowed for isolation of 2,5-bis(diphenylphosphinyl)-3,6-dihydroxy-quinone ( 4a ) and 2,5-bis(diisopropylphosphinyl)-3,6-dihydroxy-quinone ( 4b ). Compounds 1a-b  – 4a-b were fully characterized by spectroscopic methods (nuclear magnetic resonance [FT-NMR] spectroscopy, infrared [FT-IR] spectroscopy, and high resolution mass spectrometry [HRMS]); 3a-b and 4a-b were also investigated by cyclic voltammetry. Compounds 1a-b , 2a , and 4a-b were also characterized by single-crystal X-ray diffraction methods.

The ternary intermetallic phases RE Pd 2 Zn 3 ( RE  = Y, La–Nd, Sm, Gd–Dy) were synthesized from the elements by induction melting in sealed niobium ampoules followed by annealing. The CaCu 5 -type samples (space group P 6/ mmm ) were characterized through Guinier powder patterns. The structures of YPd 2 Zn 3 ( a  = 523.91(4), c  = 430.88(3) pm, wR 2 = 0.0570, 96 F 2 values, 9 variables) and NdPd 2 Zn 3 ( a  = 535.08(7), c  = 427.81(6) pm, wR 2 = 0.0217, 123 F 2 values, 9 variables) were refined from single-crystal X-ray diffractometer data. The zinc atoms form Kagome layers in AA stacking which leave trigonal prismatic voids for the palladium and hexagonal prismatic voids for the rare earth atoms. The Zn–Zn distances within the Kagome network of YPd 2 Zn 3 are 262 pm and the Pd–Zn distances in the Pd@Zn 6 trigonal prisms are 263 pm.

The complete solid solutions TbCuIn 1– x M x ( M  = Al, Ga) were studied by powder X-ray diffraction and scanning electron microscopy for samples equilibrated at T  = 873 K. The influence of In substitution by Al or Ga, the solubility ranges and the changes of unit cell parameters have been determined: TbCuIn 1.0–0 Al 0–1.0 (ZrNiAl type, space group P 6 ‾ 2 $\overline{6}2$ m , a  = 0.7457(1)–0.7035(1), c  = 0.3958(1)–0.4044(1) nm, V  = 0.1906–0.1733 nm 3 ); TbCuIn 1–0.8 Ga 0–0.2 (ZrNiAl type, a  = 0.74569(5)–0.73882(13), с  = 0.39582(3)–0.39663(14) nm, V  = 0.1906–0.1875 nm 3 ); TbCuIn 0.3–0 Ga 0.7–1.0 (KHg 2 type, Imma , а =  0.43943(9)–0.43750(5), b =  0.70833(12)–0.70537(6), с  = 0.74866(12)–0.74525(7) nm, V  = 0.2330–0.2300 nm 3 ). The crystal structure of TbCuIn 0.42(1) Al 0.58(1) was refined from single-crystal X-ray diffractometer data: ZrNiAl type, P 6 ‾ 2 $\overline{6}2$ m, a  = 0.71633(6), c  = 0.40785(3) nm, wR 2 = 0.0379, 291 F 2 values and 16 variables. The basic crystal chemical features are discussed.

A new coordination polymer {[Cd(BIPA)(DCPS)](H 2 O)} n ( 1 ) was constructed with bis(4-(1H-imidazole-1-yl)phenyl)amine and 4,4′-sulfonyldibenzoate ligands. The complex 1 features (BIPA–Cd–BIPA) n and (DCPS–Cd–DCPS) n helical chains in a 3D architecture assembled via hydrogen bonds. A spectroscopic study of complex 1 in the crystalline state showed an intense red-shifted photoluminescence as compared with the ligands BIPA and DCPS 2− , which can be attributed to the ligand-to-metal charge transfer (LMCT) transitions.

A zinc(II) coordination polymer [Zn(cyip)(bpe)] n (1) , (cyipH 2  = 5-(3-carboxybenzyloxy)-isophthalic acid, bpe = 1,2-bis(4-pyridyl)ethane), has been synthesized under hydrothermal conditions. Its structure was determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis and IR spectra. Complex 1 crystallizes in the monoclinic space group I 2/ a . In 1 , the [cyip] 2– ligand bridges the Zn(II) cations to form infinite chains, which are connected through O–H···O hydrogen bonds into layers in the form of 2-fold interpenetrated nets.

The reaction of an orthoamide derivative of phenylpropiolic acid ( 22a ) with primary and secondary amides gives rise to the formation of a wide spectrum of reaction products. The reaction of 22a with formamide delivers a N -carbamoyl-cinnamic acid amidine, wheras the analogous reaction with methylene-diformamide leads to a ketenaminal, which is substituted in β -position by a N -formylimino group. From the orthoamide 22a and phthalimide a phthalic acid amide amidine is obtained. In contrast the reaction of diformamide with 22a affords a β -imino enamine. 2,6-Diaminopyridines can be obtained from 22a with acetamide, propionamide and butyramide in low yields. The pyridines are characterized as perchlorates. From 22a and benzamide a 4-amino-2,6-diphenylpyrimidine is obtained in low yield. In the reaction of the closely related orthoamide derivative of 4-Cl-phenylpropiolic acid 22b with benzamide are isolated as a further products two pyrimidine derivatives. A pyrimidinone and a vinylogous thiourea can be obtained from 22a and urea and thiourea, respectively.