1-(Phenyl-sulfon-yl)-1H-indole-2-carbaldehyde.

The title compound, C15H11NO3S, was prepared by a facile synthetic approach. The N atom in the pyrrole ring of the indole moiety is pyramidal (bond-angle sum = 350.0°) and the phenyl ring of the phenyl-sulfonyl motif forms a dihedral angle of 76.24 (7)° with the mean plane of the indole ring system. In the crystal, C-H⋯O and C-H⋯π inter-actions link the mol-ecules into a three-dimensional network.

Dopant-Free Hole-Transport Materials with Germanium Compounds Bearing Pseudohalide and Chalcogenide Moieties for Perovskite Solar Cells.

Hole-transport materials (HTMs) are key electronic components for the functioning of perovskite solar cells (PSCs) as they extract the photogenerated holes from the perovskite to be transported subsequently to the back electrode while minimizing the loss from electron recombination. Herein, we report the synthesis and characterization of novel germanium-based compounds with [{HC(CMeNAr)2}GeNCS] (2), [{HC(CMeNAr)2}Ge(S)NCS] (3), and [{HC(CMeNAr)2}Ge(Se)NCS] (4) compositions, with Ar = 2,6-iPr2C6H3 and the photovoltaic performance of 3 and 4 that is the same as for HTM in PSC. All compounds displayed excellent thermal properties and an appropriate alignment of energy levels for the perovskite with maximum optical absorption in the near-UV region. As revealed by space-charge limited-current (SCLC) measurements, compounds 3 and 4 have competing hole mobilities of about 1.37 × 10-4 and 4.88 × 10-4 cm2 V-1 s-1, respectively. Upon assessing PSC devices using 3 and 4 with triple-cation perovskite absorber Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3, the power conversion efficiencies (PCEs) were about 13.03 and 9.23%, respectively, both without doping and additives, and were compared with benchmark HTM spiro-OMeTAD (2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene). Quantum chemical calculations with DFT showed that the optoelectronic properties are strongly influenced by the combined contributions of the germanium atom, the pseudohalide moiety (NCS-), and chalcogenides (S2- or Se2-). Fine tuning the electronic properties of germanium is thus a good strategy for the targeted synthesis of potential conducting molecules in PSCs.

Crystal structures and biological activity of 1,1,4-triphenyl-substituted 1,3-enyne compounds.

1,3-Enyne structural motifs are versatile building blocks in organic synthesis and occur widely in various natural products with many of them being highly active as cytotoxic macrolides and antitumour antibiotics. This article presents the crystal structure of three 1,1,4-triphenyl-substituted 1,3-enynes, viz. 4-(2-methylphenyl)-1,1-diphenylbut-1-en-3-yne, C23H18 (1), 4-(2-methoxyphenyl)-1,1-diphenylbut-1-en-3-yne, C23H18O (2), and 4-(4-nitrophenyl)-1,1-diphenylbut-1-en-3-yne, C22H15NO2 (3). The benzene ring at position 4 of the but-1-en-3-yne group bears a weakly activating methyl group in compound 1, a moderately activating methoxy group in 2 and a strongly deactivating nitro group in 3. The crystal structures of 1 and 3 both have monoclinic symmetry, while that of 2 is orthorhombic, and all of them have one molecule in the asymmetric unit. All three compounds were investigated for their antibacterial and antifungal activities. Interestingly, enyne 2 is the only compound tested that inhibited the growth of Aspergillus niger.

Tetra-aqua-bis-(2,3-di-hydro-1,4-benzodioxine-2-carboxyl-ato)calcium(II).

The acid-base reaction of 1,4-benzodioxane 2-carb-oxy-lic acid with calcium carbonate furnished the centrosymmetric title compound, [Ca(C9H7O4)2(H2O)4], in which the metal ion is octa-hedrally coordinated by two monodentate 1,4-benzodioxane 2-carboxyl-ate ligands and four water mol-ecules. In the crystal, O-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network.

Crystal structure of 4-[(adamantan-1-yl)amino]-naphthalene-1,2-dione.

The title compound, C20H21NO2, an example of a stable 1,2-naphtho-quinone, was determined by single-crystal X-ray diffraction analysis at 100 K. This structure illustrates steric buttressing of the adamantanyl group, forcing the N-H group into the coplanar aromatic C-H. The presence of strong delocalization between the planar N atom at the 4-position and the carbonyl group at the 2-position is indicated. In the crystal, C-H⋯O and C-H⋯π inter-actions link the mol-ecules into a three-dimensional network.

Crystal structure of (E)-2-(tert-butyl-amino)-4-(tert-butyl-imino)-naphthalen-1(4H)-one.

The title compound, C18H24N2O, is the first example of a naphtho-quinone imine derivative isolated in the 4-imine/2-amine tautomeric form having bulky alkyl substituents at the N atoms. The mol-ecular conformation is stabilized by an intra-molecular hydrogen bond between the amine and a carbonyl group and by London attraction between the two tert-butyl groups. Only van der Waals inter-actions were identified in the crystal packing.

OH functionality of germanium(II) compounds for the formation of heterobimetallic oxides.

Two novel germanium(II) mu-oxo heterobimetallic oxides with different oxidation states at the metal centers have been reported. The reaction of LGeOH [L = N(Ar)C(Me)CHC(Me)N(Ar) (Ar = 2,6-i-Pr(2)C(6)H(3))] with Cp(2)MMe(2) (M = Zr, Hf) in Et(2)O afforded LGeOM(Me)Cp(2) [M = Zr (2), Hf (3)] in moderate yield. Compounds 2 and 3 were characterized by elemental analysis, IR, NMR, EI-MS, and single X-ray structural analysis. Compounds 2 and 3 crystallized in the space group P, and the geometry at the metal centers is tetrahedral. The Ge-O bond lengths of 2 and 3 are very similar (1.797(2) and 1.799(3) Angstroms, respectively), and a bent M-O-M' angle in 2 (143.8(1) degrees) and 3 (141.9(2) degrees) features both oxide systems. Different orientations of the Cp and Me groups of the metal centers were observed, and deviations of the Cp groups were exhibited.