scholarly journals The Crystal Structure of the Polymerization Catalyst of Acetaldehyde and Its Derivatives. II. The Crystal and Molecular Structure of the Trimethylamine Oxide Adduct of DimethylaluminumN-Phenylbenzimidate, [(CH3)2Al·O·C(C6H5):N(C6H5), ON(CH3)3]

1972 ◽  
Vol 45 (11) ◽  
pp. 3388-3396 ◽  
Author(s):  
Yasushi Kai ◽  
Noritake Yasuoka ◽  
Nobutami Kasai ◽  
Masao Kakudo
1984 ◽  
Vol 62 (3) ◽  
pp. 601-605 ◽  
Author(s):  
Masood A. Khan ◽  
Clovis Peppe ◽  
Dennis G. Tuck

The crystal structure of the title compound has been determined by the heavy atom method. The crystals are orthorhombic, space group Pbca, with unit cell dimensions a = 22.795(3) Å, b = 17.518(2) Å, c = 12.396(3) Å, Z = 8; R = 0.0409 for 1527 unique "observed" reflections. The structure is disordered, with each halogen site (X) occupied by 75% Br, 25% I. The molecule consists of two X2(tmen)In units (tmen = N,N,N′,N′-tetramethylethanediamine) with distorted trigonal bipyramidal geometry, joined by an In—In bond 2.775(2) Å in length.


1980 ◽  
Vol 33 (6) ◽  
pp. 1323 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
PE Davies ◽  
CLWAH Raston

The heterocyclic derivatives, 8,9-dimethoxy-3-methyl-1-phenyl-3,4,5,6- tetrahydro-1H-2,3-benzoxazocine(3a) and 9,10-dimethoxy-3-methyl-1- phenyl-1,3,4,5,6,7-hexahydro-2,3-benzoxazonine (3b),examples of two new ring systems, have been prepared by Meisenheimer rearrangement of the corresponding 2-benzazepine and 2-benzazocine N-oxide derivatives (2a) and (2b). The Bischler-Napieralski-type cyclization reaction was used in the preparation of the tertiary amine precursors of these N-oxides reaction conditions for the cyclization were critical and phosphorus oxychloride in refluxing butanenitrile was found to give the best yields of the seven- or eight-membered cyclic imine intermediates. Reductive cleavage of the benzoxazocine derivative (3a) with zinc in acetic acid followed by N-methylation gave the expected product, [2-{3- (dimethylamino)propyl}-4,5-di-methoxyphenyl]phenylmethanol (12). The crystal and molecular structure of (3a) has been determined by X-ray crystallographic analysis.


1979 ◽  
Vol 34 (3) ◽  
pp. 434-436 ◽  
Author(s):  
A. Müller ◽  
S. Pohl ◽  
M. Dartmann ◽  
J. P. Cohen ◽  
J. M. Bennett ◽  
...  

Abstract The novel tri-nuclear metal-sulfur cluster [Mo3S(S2)6]2- can be obtained as its ammonium salt by the reaction of a Moiv containing aqueous solutions with polysulfide. Its crystal and molecular structure has been determined by a single crystal X-ray study. The crystals are monoclinic (space group Cm, with a = 11.577(6) Å, b = 16.448(7) Å, c = 5.716(2) Å, β = 117.30(3)°, V = 967.2 Å3 , Z = 2, dexptl. = 2.54(2) g/cm3 , dcal = 2.54 g/cm3). The structure consists of isolated [Mo3S(S2)6]2- units, with three Mo atoms at the vertices of a triangle. There are bridging as well as terminal S22--ligands lying above and below the Mo3-plane (bond distances: Mo-Mo = 2.722 Å, Mo-S(terminal) = 2.435, Mo-S(bridging) = 2.452, Mo3-S = 2.353(4) Å and S-S = 2.04 Å (mean values)).


1988 ◽  
Vol 41 (3) ◽  
pp. 293 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
LM Engelhardt ◽  
IWK Gunawardana ◽  
AH White

Meisenheimer rearrangement of the N-oxides (4) derived from a series of 5-aryl-4-methyl-2,3,4,5-tetrahydro-1,4-benzoxazepines (3) gave rise to eight derivatives (5) of the new 2H,6H-1,5,4-benzodioxazocine ring system. Reaction of 9-methoxy-5-methyl-6-phenyl-3,4,5,6- tetrahydro-2H-1,5-benzoxazocine (6) with 3-chloroperoxybenzoic acid gave an unstable N-oxide (7). A Meisenheimer rearrangement product from (7), 10-methoxy-5-methyl-7-phenyl-2,3,4,5-tetrahydro-7 H-1,6,5- benzodioxazonine (8), the first example of this ring system, was isolated directly in moderate yield on oxidation of (6) with cooling. The crystal and molecular structure of (8) has been determined by X-ray crystallographic methods.


1986 ◽  
Vol 51 (11) ◽  
pp. 2521-2527 ◽  
Author(s):  
Jan Lokaj ◽  
Eleonóra Kellö ◽  
Viktor Kettmann ◽  
Viktor Vrábel ◽  
Vladimír Rattay

The crystal and molecular structure of SnBu2(pmdtc)2 has been solved by X-ray diffraction methods and refined by a block-diagonal least-squares procedure to R = 0.083 for 895 observed reflections. Monoclinic, space group C2, a = 19.893(6), b = 7.773(8), c = 12.947(8) . 10-10 m, β = 129.07(5)°, Z = 2, C20H38N2S4Sn. Measured and calculated densities are Dm = 1.38(2), Dc = 1.36 Mg m-3. Sn atom, placed on the twofold axes, is coordinated with four S atoms in the distances Sn-S 2.966(6) and 2.476(3) . 10-10 m. Coordination polyhedron is a strongly distorted octahedron. Ligand S2CN is planar.


1997 ◽  
Vol 52 (2) ◽  
pp. 256-258 ◽  
Author(s):  
Evgeni V. Avtomonov ◽  
Rainer Grüning ◽  
Jörg Lorberth

Abstract The crystal structure of the title compound has been determined by X-ray diffraction methods. Due to the Lewis acidic character of the iodine substituent a “zig-zag” chain is formed via intermolecular interactions (2.933(4) A) between iodine and oxygen atoms of theocarbamate moiety. A three-dimensional network is formed through hydrogen-bridging (2.04 A) between NH-groups and the oxygen atoms of the neighbouring carbamate group of the next molecule.


1982 ◽  
Vol 37 (12) ◽  
pp. 1499-1503 ◽  
Author(s):  
Heinrich Nöth

Mg(BH4)2 • 3 THF was prepared from MgHo and B2H6 in tetrahydrofuran. It crystallizes monoclinically, space group C2/c, Z = 4. The crystal structure reveals that the molecule contains a seven-coordinate Mg center. Its BH4 groups form double hydrogen bridges to magnesium. The geometry at Mg corresponds to a slightly distorted trigonal bipyramid for the O 3 B 2 (Mg)-coordination polyhedron, with two THF molecules in apical and one in equatorial position. A two-fold crystallographic axis passes through Mg and the equatorial oxygen atom thus posing C2 symmetry on the molecule


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