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1.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 7): o1533, 2009 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21582822

RESUMO

The title compound, C(24)H(22)O(4)S, was prepared by reaction between (2E)-3-(6-meth-oxy-2-naphth-yl)-1-(2-thien-yl)prop-2-en-1-one and ethyl acetoacetate. In the crystal, the cyclo-hexenone ring shows a distorted half-chair conformation. The length of the double bond in the cyclohexenone ring [1.343 (4) Å] is normal.

2.
Acta Crystallogr C ; 56(Pt 4): E124-5, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15263172

RESUMO

The refinements described here for (NEt(4))[ZnI(4)] completely confirm the results previously obtained for the isostructural tetrabromocadmate at room temperature [Geselle & Fuess (1994). Acta Cryst. C50, 1582-1585]. Here again, isolated MX(4) (M = Zn and X = I) tetrahedra are accompanied by two cations in a 'swastika' conformation and a third in a virtually planar trans conformation. One of the former cations is particularly disordered.

3.
Acta Crystallogr C ; 57(Pt 8): 891-2, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11498602

RESUMO

Hydrothermally prepared ethylenediammonium beryllophosphate, (C(2)H(10)N(2))(0.5)[BePO(4)], is an analogue of aluminosilicate zeolite gismondine. A three-dimensional network of vertex-sharing BeO(4) and PO(4) tetrahedra [d(av)(Be-O) = 1.618 (3) A, d(av)(P-O) = 1.5246 (14) A and straight theta(av)(Be-O-P) = 139.8 degrees] encapsulates the disordered ethylenediammonium cations in an eight-ring channel system.

4.
Acta Crystallogr C ; 57(Pt 1): 2-3, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11173376

RESUMO

Nasicon-type trisodium discandium tris(arsenate), Na3Sc2(AsO4)3, contains a polyhedral network of vertex-sharing octahedral ScO6 and tetrahedral AsO4 units [d(av)(Sc-O) = 2.089 (2) A and d(av)(As-O) = 1.672 (2) A] encapsulating two types of Na+ species. The sodium site occupancies are similar to those of the equivalent species in beta-Na3Sc2(PO4)3.

5.
Acta Crystallogr C ; 57(Pt 5): 508-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11353230

RESUMO

The title compound, (NH(4))ZnPO(4)-HEX, is built up from a three-dimensional network of ZnO(4) and PO(4) tetrahedra [d(av)(Zn-O) = 1.9400 (7) A and d(av)(P-O) = 1.5396 (7) A], fused together via Zn-O-P links [straight theta(av) = 133.47 (4) degrees ]. An undisordered linear Zn-O-P bond occurs (all three atoms lie on a threefold axis). Extra-framework NH(4)(+) cations, which interact with the [ZnPO(4)](-) framework by hydrogen bonds, complete the crystal structure.

6.
Acta Crystallogr B ; 57(Pt 2): 190-200, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11262434

RESUMO

In bis(4-tolyl) sulfone, C(14)H(14)O(2)S (1), 2,5,4'-trimethyldiphenyl sulfone, C(15)H(16)O(2)S (2), and 4-chlorodiphenyl sulfone, C(12)H(9)ClO(2)S (3), the molecules are linked by soft C-H...O hydrogen bonds into three different types of one-dimensional aggregate: simple chains in (1), molecular ladders in (2) and chains of fused rings in (3). In each of 3,4-dimethyl-4'-chlorodiphenyl sulfone, C(14)H(13)ClO(2)S (4), and 2,5-dimethyldiphenyl sulfone, C(14)H(14)O(2)S (5), the C-H...O hydrogen bonds link the molecules into two different types of two-dimensional sheet, based on a (4,4) net in (4) and a (3,6) net in (5). The patterns of soft C-H...O hydrogen bonds in (1)-(5) are compared with those in other diaryl sulfones, mainly retrieved from the Cambridge Structural Database, whose substitution patterns preclude the formation of hard hydrogen bonds. Observed aggregation modes range from the formation of no C-H...O hydrogen bonds at all, via finite (zero-dimensional) arrays through one-, two- and three-dimensional systems.

7.
Acta Crystallogr C ; 57(Pt 3): 271-2, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11250574

RESUMO

In the title complex, [Cu(C(7)H(4)NO(3)S)(2)(C(2)H(7)NO)(2)], the Cu(II) centre lies on an inversion centre and exhibits octahedral coordination, with the two ethanolamine (Hea) and two saccharinate [sac; anionic 1,2-benzisothiazol-3(2H)-one 1,1-dioxide] ligands in a trans configuration. The bidentate Hea ligands bridge axial and equatorial positions and the sac anions occupy equatorial sites around the distorted octahedral copper(II) centre [Cu--O = 2.3263 (16), Cu--N(Hea) = 1.9923 (16) and Cu--N(sac) = 2.1776 (16) A].


Assuntos
Compostos Organometálicos/química , Sacarina/análogos & derivados , Sacarina/química , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular
11.
Inorg Chem ; 40(25): 6518-20, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11720513
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