The metal template effect on O-alkylation of tetrahydroxy[3.1.3.1]metacyclophane with 4-(chloromethyl)pyridine to afford tetrakis- [(4-pyridylmethyl)oxy][3.1.3.1]metacyclophanes and their conformational studies

2001 ◽  
Vol 79 (10) ◽  
pp. 1422-1430 ◽  
Author(s):  
Takehiko Yamato ◽  
Kenji Kumamaru ◽  
Hirohisa Tsuzuki
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Pyridine Ring ◽  
Benzyl Bromide ◽  
Major Product ◽  
Template Effect ◽  
Substitution Product ◽  
Conformational Studies ◽  
No Formation

An attempted O-alkylation of the flexible macrocycle tetrahydroxy[3.1.3.1]metacyclophane (1) with 4-(chloromethyl) pyridine (2a) in the presence of NaH under THF reflux gave 1,3-di-O-substitution product distal-3a as a major product. In contrast, tetraol 1 was O-alkylated with 2a in the presence of Cs2CO3 to afford a mixture of two conformers of tetra-O-alkylated product 4a in a ratio of 77:23 (1,4-alternate-4a:partial-cone-4a) in 95% yield. No formation of the cone conformer in the reaction of the tetraol 1 with 2a, in comparison with those with 2-(chloromethyl) pyridine (2b) or benzyl bromide (2c) in the presence of NaH or K2CO3, which predominantly afforded cone-conformer, might be attributable to the absence of contributions derived from cation–N interactions as well as cation–π interactions. The latter effect might be much smaller because of the decreased π-density of the pyridine ring compared to that of the benzene ring. The structural characterization of these products in solution as well as solid state is also discussed.Key words: macrocycles, calixarenes, cyclophanes, [3.1.3.1]metacyclophanes, O-alkylation, conformation, crystal structure, cation–N interaction.

Synthesis, conformational studies, and inclusion properties of tris[(2-pyridylmethyl)oxy]hexahomotrioxacalix[3]arenes

1998 ◽  
Vol 76 (7) ◽  
pp. 989-996 ◽  
Author(s):  
Takehiko Yamato ◽  
Mitsuteru Haraguchi ◽  
Jun-Ichi Nishikawa ◽  
Seiji Ide ◽  
Hirohisa Tsuzuki
Keyword(s):  
Alkylation Reaction ◽  
Alkali Metal Cations ◽  
Template Effect ◽  
Two Phase ◽  
Conformational Studies ◽  
Preferential Formation ◽  
H Nmr ◽  
Inclusion Properties ◽  
Partial Cone

O-Alkylation of the flexible macrocycle 1 with 2-(chloromethyl)pyridine in the presence of Cs2CO3 resulted in the preferential formation of partial-cone-2. The cone-to-partial-cone ratio of 2 increased in the presence of K2CO3, and led to almost equal in the presence of NaH. The template effect of the alkali metal cations plays an important role in this O-alkylation reaction. The structural characterization of these products is also discussed. The two-phase solvent extraction data indicated that tris[(2-pyridylmethyl)oxy]hexahomotrioxacalix[3]arenes 2 show moderate extractability for n-butylammonium ion and high extractability for Ag+. The 1H NMR titration of cone-2 with AgSO3CF3 clearly demonstrates that a 1:1 complex is formed, which is stable on the NMR time scale. Thus, the synergism of cyclophane moiety and two or three lower-rim side chains with pyridyl groups play a significant role on the complexation of tris[(2-pyridylmethyl)oxy] derivatives cone-2 and partial-cone-2 with Ag+ ion and n-butylammonium ion.Key words: macrocycles, calixarenes, O-alkylation, ionophores, cation-N interaction.

Corrigendum to “Synthesis, crystal structure and characterization of iron pyroborate (Fe2B2O5) single crystals” [J. Solid State Chem. 182 (2009) 2004–2009]

2009 ◽  
Vol 182 (10) ◽  
pp. 2947 ◽  
Author(s):  
Tetsuya Kawano ◽  
Haruhiko Morito ◽  
Takahiro Yamada ◽  
Takeyoshi Onuma ◽  
Shigefusa F. Chichibu ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Single Crystals

Mono- and difunctional furan-based 1,2,3,5-dithiadiazolyl radicals; preparation and solid state structures of 2,5-[(S2N2C)OC4H2(CN2S2)] and 2,5-[(S2N2C)OC4H2(CN)]

1992 ◽  
Vol 70 (3) ◽  
pp. 919-925 ◽  
Author(s):  
A. Wallace Cordes ◽  
Charles M. Chamchoumis ◽  
Robin G. Hicks ◽  
Richard T. Oakley ◽  
Kelly M. Young ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Crystal Structures ◽  
Monoclinic Space Group ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
The Mean ◽  
Solid State Structures ◽  
Solid State Characterization

The preparation and solid state characterization of the bifunctional radical furan-2,5-bis(1,2,3,5-dithiadiazolyl) 2,5-[(S2N2C)OC4H2(CN2S2)] and the related monofunctional radical 2-cyanofuran-5-(1,2,3,5-dithiadiazolyl) 2,5-[(S2N2C)OC4H2(CN)] are described. The crystal structure of 2,5-[(S2N2C)OC4H2(CN2S2)] is orthorhombic, space group Pna21, and consists of interleaved arrays of dimers, for which the mean interannular [Formula: see text] contact is 3.137 Å. The crystal structure of the monofunctional radical 2,5-[(S2N2C)OC4H2(CN)] is monoclinic, space group P21/n, and consists of a ribbon-like network of dimers (mean interannular [Formula: see text] interconnected by close head-to-tail [Formula: see text] contacts. The dimer units form stacks parallel to z, with a mean interdimer [Formula: see text] separation of 3.956 Å. The similarities and differences between these two crystal structures and those of related benzene-substituted systems are discussed. Keywords: dithiadiazolyl radicals, furan-based diradicals, cyanofuran-based radicals, radical dimers, crystal structures.

Erste strukturelle Charakterisierung eines leicht oxidierbaren 1,4-Dihydrochinoxalin-Derivats / First Structural Characterization of an Easily Oxidized Derivative of 1,4-Dihydroquinoxaline

1993 ◽  
Vol 48 (6) ◽  
pp. 713-718 ◽  
Author(s):  
Alexander Lichtblau ◽  
Hans-Dieter Hausen ◽  
Wolfgang Kaim
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Dihedral Angle ◽  
Structural Characterization ◽  
Crystal Structure Analysis ◽  
Ring System ◽  
Structural Flexibility ◽  
Steric Repulsion ◽  
Alkyl Groups

The first crystal structure analysis of a 1,4-dihydroquinoxaline is described by example of the 1,4-bis(tert-butyldimethylsilyl) derivative. In the solid state, this molecule exhibits a nonplanar heterocycle with a dihedral angle of 156.3° along the N—N axis in the boat-shaped 8π electron ring system. The alkyl groups of the Si(tert-Bu)Me2 substituents are arranged as to minimize steric repulsion. Despite the reduced π electron conjugation due to non-planarity, the compound is oxidized reversibly to an EPR detectable radical cation at —0.59 V vs. ferrocene in dichloromethane. However, the second oxidation to the fully aromatic dication is electrochemically irreversible. A comparison with previously obtained results illustrates the structural flexibility of the non-aromatic 1,4-dihydro-1,4-diazine ring system which is strongly affected by rather weak non-bonded interactions.

scholarly journals Spiropyran salts and their neutral precursors: synthesis, crystal structure, photochromic transformations in solutions and solid state

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
E.A. Yurieva ◽  
S.M. Aldoshin
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Pyridine Ring ◽  
Photochromic Properties ◽  
X Ray ◽  
Photochromic Transformations ◽  
The Relationship

AbstractThis review covers investigations of spiropyran iodides with N-substituted indoline fragment, and with the pyran cycle being annelated to N-methylated pyridine ring. The schemes of synthesis of iodides and their neutral precursors, as well as results of X-ray analysis and photochemical study of the crystals of the obtained compounds are presented. Based on our and literature data, the relationship between the structure and photochromic properties has been discussed for a series of salts and neutral pyridospiropyrans.

Synthesis and structural characterization of Li3Y(BO3)2

2017 ◽  
Vol 72 (2) ◽  
pp. 153-158 ◽  
Author(s):  
Sebastian Bräuchle ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Solid State ◽  
Boric Acid ◽  
Structural Characterization ◽  
Diffraction Data ◽  
Lithium Carbonate ◽  
X Ray Diffraction ◽  
X Ray

AbstractLi3Y(BO3)2 was prepared by high-temperature solid state synthesis at 900°C in a platinum crucible from lithium carbonate, boric acid, and yttrium(III) oxide. The compound crystallizes monoclinically in the space group P21/c (no. 14) (Z=4) isotypically to Li3Gd(BO3)2. The structure was refined from single-crystal X-ray diffraction data: a=8.616(3), b=6.416(3), c=10.014(2) Å, β=116.6(2)°, V=494.9(3) Å3, R1=0.0211, and wR2=0.0378 for all data. The crystal structure of Li3Y(BO3)2 consists of [Y2O14] dinuclear units, which are interconnected to each other by planar B(1)O3 groups and LiO4 tetrahedra via common edges and corners along the a axis.

Synthesis and characterization of molybdenum–tin complexes derived from the molybdenum tricarbonyl anion, [MeGapz3]Mo(CO)3−, and organotin chlorides. X-ray crystal structure of [MeGapz3]Mo(CO)3SnPh3 (where pz = pyrazolyl, N2C3H3)

1986 ◽  
Vol 64 (2) ◽  
pp. 321-327 ◽  
Author(s):  
Emmanuel C. Onyiriuka ◽  
Steven J. Rettig ◽  
Alan Storr
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Heavy Atom ◽  
Synthesis And Characterization ◽  
Full Matrix ◽  
X Ray ◽  
Tin Complexes ◽  
Interesting Solution ◽  
Single Bonds

The reaction of the molybdenum tricarbonyl anion, [MeGapz3]Mo(CO)3−, with the organotin chlorides, Ph3SnCl, Me3SnCl, and Me2SnCl2, has yielded a series of complexes in which direct Mo—Sn single bonds are featured. The [MeGapz3]Mo(CO)3SnMe2Cl complex shows an interesting solution behavior in which a transition from a 3:4, or piano stool structure, to a 3:3:1, or capped octahedral arrangement, is thought to occur. The 3:3:1 structure has been demonstrated in the solid state for the [MeGapz3]Mo(CO)3SnPh3 compound by means of a crystal structure determination. Crystals of [methyltris(1-pyrazolyl)gallato-N,N,N](triphenylstannyl)tricarbonylmolybdenum are monoclinic, a = 11.4439(8), b = 19.5116(8), c = 15.2686(12) Å β = 111.370(3)°, Z = 4, space group P21/c. The structure was solved by conventional heavy-atom methods and was refined by full-matrix least-squares procedures to R = 0.025 and Rw = 0.031 for 5259 reflections with I ≥ 3σ(I). Important bond lengths include: Mo—Sn = 2.8579(3), Mo—N = 2.239(2)–2.244(2), Mo—C = 1.967(3)–2.000(3), Sn—C = 2.151(3)–2.166(3), Ga—N = 1.920(3)–1.931(3), and Ga—C = 1.943(4) Å.

scholarly journals Solid-State Characterization of Candesartan Cilexetil (TCV-116): Crystal Structure and Molecular Mobility.

1999 ◽  
Vol 47 (2) ◽  
pp. 182-186 ◽  
Author(s):  
Hirokazu MATSUNAGA ◽  
Taro EGUCHI ◽  
Koji NISHIJIMA ◽  
Toshio ENOMOTO ◽  
Kazumichi SASAOKI ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Molecular Mobility ◽  
Candesartan Cilexetil ◽  
Solid State Characterization
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