The crystal structures of 2-endo-acetyl and 2-endo-carbomethoxy-1,4-epoxy-6,7-dimethoxy-1,2,3,4-tetrahydronaphthalenes

1984 ◽  
Vol 62 (6) ◽  
pp. 1099-1102 ◽  
Author(s):  
N. J. Taylor ◽  
B. A. Keay ◽  
R. Rodrigo
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Direct Methods ◽  
Full Matrix ◽  
Space Group

Crystals of 2-endo-acetyl-1,4-epoxy-6,7-dimethoxy-1,2,3,4-tetrahydronaphthalene are orthorhombic, a = 5.524(1), b = 8.929(1), c = 25.479(4) Å, Z = 4, space group P212121; those of 2-endo-carbomethoxy-1,4-epoxy-6,7-dimethoxy-1,2,3,4-tetrahydronaphthalene are monoclinic, a = 10.878(2), b = 6.634(1), c = 18.224(4) Å, β = 92.76(2)°, Z = 4, space group P21/c. Both structures were solved by direct methods and refined by full-matrix least-squares methods to final R values of 0.041 and 0.036 for 875 and 1327 reflections with I ≥ 3σ(I) respectively.

Structural studies of organoboron compounds. XXXII. 5,5-Difluoro-2,2-pentamethylene-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene and 2,2-pentamethylene-5,5-diphenyl-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene

1988 ◽  
Vol 66 (10) ◽  
pp. 2621-2630 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Mahmood Tajerbashi ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Solid State ◽  
Physical Properties ◽  
Least Squares ◽  
Crystal Structures ◽  
Direct Methods ◽  
Structural Studies ◽  
Full Matrix ◽  
Space Group ◽  
Bond Lengths ◽  
Conformational Isomers

Details of the syntheses, physical properties, and crystal structures of the title compounds are reported. Crystals of 5,5-difluoro-2,2-pentamethylene-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene are triclinic, a = 6.1576(3), b = 11.2651(3), c = 10.8118(3) Å, α = 109.747(3), β = 105.807(4), γ = 92.976(4)°, Z = 2, space group [Formula: see text], and those of 2,2-pentamethylene-5,5-diphenyl-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene are monoclinic, a = 9.8549(6), b = 10.9242(6), c = 41.263(2) Å, β = 92.717(6)°, Z = 8, space group P21/n. Both structures were solved by direct methods and were refined by full-matrix least-squares procedures to R = 0.045 and 0.042 for 2344 and 4248 reflections with I ≥ 3σ(I), respectively. The molecules were both found to possess a seven-membered chelate structure, the O,O-chelatїng ligand being strongly bound to the X2B moiety. Two conformational isomers of the X = Ph compound were found in the solid state. The 2-oxazoline N-oxide moieties present in both compounds are the first to be structurally characterized. Important mean libration-corrected bond lengths are: O—B = 1.491 and F—B = 1.387 Å for X = F; O—B = 1.511 and C—B = 1.620 Å for X = Ph.

Aromatic aldonitrones of 2-(hydroxyamino)benzyl alcohol and their cyclic isomers. Crystal and molecular structures of a 1-hydroxy-1,2-dihydro-4H-3,1-benzoxazine, a boron chelate, and its parent nitrone ligand

1998 ◽  
Vol 76 (4) ◽  
pp. 389-399 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Jörg Metge ◽  
Steven J Rettig ◽  
James Trotter
Keyword(s):  
Least Squares ◽  
Benzyl Alcohol ◽  
Crystal Structures ◽  
Direct Methods ◽  
Molecular Structures ◽  
Full Matrix ◽  
Space Group ◽  
Crystal And Molecular Structures ◽  
Independent Molecules ◽  
Boron Chelate

The synthesis of a series of C-aryl-N-[2-(hydroxymethyl)phenyl]nitrones, 5 (that can also exist under certain conditions as isomeric 1-hydroxy-2-aryl-1,2-dihydro-4H-3,1-benzoxazines, 8), via 2-(hydroxyamino)benzyl alcohol, 4, and their subsequent reactions with oxybis(diphenylborane), (Ph2B)2O, leading to the 5-(arylmethylene)-7,7-diphenyl-6,8-dioxa- 5-azonia-7-borata-5H-6,7,8,9-tetrahydrobenzocyclo- heptenes 6 are described. Crystals of 1-hydroxy-2- (4-methoxyphenyl)- 1,2-dihydro-4H-3,1-benzoxazine, 8b, are monoclinic, a = 9.379(2), b = 10.699(2), c = 12.9392(7) Å, β = 99.916(2)°, Z = 4 (two independent molecules), space group Pa; those of C-[4-(dimethylamino)phenyl]-N-[(2-hydroxymethyl)phenyl]nitrone, 5c, are monoclinic, a = 7.687(1), b = 7.891(1), c = 11.5053(9) Å, β = 92.781(9)°, Z = 2, space group P21; and those of 5-[4-(dimethylamino)phenylmethylene]-7,7-diphenyl-6,8-dioxa-5-azonia-7-borata-5H-6,7,8,9- tetrahydro-benzocycloheptene, 6a, are monoclinic, a = 10.771(1), b = 13.1057(9), c = 16.8724(7) Å, β = 90.005(5)°, Z = 4, space group P21/n. The structures were solved by direct methods and refined by full-matrix least-squares procedures to R(F2) = 0.120 (Rw(F2) = 0.135) for all 3149 reflections (R(F) = 0.071, Rw(F) = 0.063 for 1500 reflections with I >3 σ (I)) for 8b and R(F) = 0.035 and 0.036 (Rw(F) = 0.031 and 0.038) for 1071 and 3594 reflections with I >3 σ (I), respectively, for 5c and 6a. Compound 8b is the first structurally characterized 1-hydroxy-1,2-dihydro-4H-3,1-benzoxazine derivative and 6a features a relatively rare seven-membered boron-containing heterocycle.Key words: C-aryl-N-[2-(hydroxymethyl)phenyl]nitrones, 1-hydroxy-2-aryl-1,2-dihydro-4H-3,1-benzoxazines, organoboron compounds, crystal structures

Structural studies of organoboron compounds. XXVII. (3-Hydroxy-2-methyl-4-pyridinonato)diphenylboron and (3-hydroxy-1,2-dimethyl-4-pyridinonato)diphenylboron

1988 ◽  
Vol 66 (1) ◽  
pp. 132-138 ◽  
Author(s):  
William O. Nelson ◽  
Chris Orvig ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Direct Methods ◽  
Structural Data ◽  
Structural Studies ◽  
Organoboron Compounds ◽  
Full Matrix ◽  
Space Group ◽  
Bond Lengths ◽  
Oxygen Atoms

Details of the preparation and crystal structures of the title compounds are given. Crystals of (3-hydroxy-2-methyl-4-pyridinonato)diphenylboron, 1, are orthorhombic, a = 13.4010(6), b = 15.005(1), c = 14.833(1) Å, Z = 8, space group Pbca, and those of (3-hydroxy-1,2-dimethyl-4-pyridinonato)diphenylboron, 2, are monoclinic, a = 8.2617(5), b = 12.374(1), c = 16.104(1) Å, β = 92.741(5)°, Z = 4, space group P21/n. Both structures were solved by direct methods and were refined by full-matrix least-squares procedures to R = 0.047 and 0.071 for 1654 and 1831 reflections with I ≥ 3σ(I), respectively. Both molecules contain five-membered C2O2B chelate rings, that in 2 being nearly planar. Structural data indicate weaker overall binding of the ligand oxygen atoms to boron in 1 than in 2. Bond lengths (corrected for libration) are O—B = 1.497(5) and 1.650(5), C—B = 1.600(5) and 1.599(5) Å for 1; O—B = 1.542(5) and 1.569(5), C—B = 1.607(6) and 1.609(6) Å for 2.

Structural studies of organoboron compounds. XXXIV. 4-(N-Methoxymethylimino)-2,2-diphenyl-1,3-dioxa-2-borata-1,2,3,4-tetrahydronaphthalene and 4-diethylimino-2,2-diphenyl-1,3-dioxa-2-borata-1,2,3,4-tetrahydronaphthalene

1989 ◽  
Vol 67 (10) ◽  
pp. 1636-1643 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Mahmood Tajerbashi ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Physical Properties ◽  
Least Squares ◽  
Crystal Structures ◽  
Direct Methods ◽  
Structural Studies ◽  
Boron Compounds ◽  
Organoboron Compounds ◽  
Full Matrix ◽  
Space Group ◽  
Bond Lengths

Details of the syntheses, physical properties, and crystal structures of the title compounds are reported. Crystals of 4-(N-methoxymethylimino)-2,2-diphenyl-1,3-dioxa-2-borata-1,2,3,4-tetrahydronaphthalene, 4, are monoclinic, a = 9.8072(5), b = 9.6217(7), c = 19.6793(12) Å, β = 94.871(5)°, Z = 4, space group P21/c, and those of 4-diethylimino-2,2-diphenyl-1,3-dioxa-2-borata-1,2,3,4-tetrahydronaphthalene, 9, are orthorhombic, a = 17.0593(7), b = 16.1372(6), c = 14.3753(5) Å, Z = 8, space group Pbca. Both structures were solved by direct methods and were refined by full-matrix least-squares procedures to R = 0.046 and 0.038 for 2198 and 2969 reflections with I ≥ 3σ(I), respectively. In both structures the N,N-dialkylsalicylamidate ligands coordinate the diphenylboron moieties via the phenolate oxygen and amide oxygen atoms, forming six-membered O—B—O chelate rings. The O(ar)—B, O(amide)—B, and mean C—B bond lengths (corrected for libration) are as follows: 1.490(3), 1.549(4), and 1.612 Å for 4 and 1.494(2), 1.550(2), and 1.612 Å for 9. Keywords: crystal structures, boron compounds, organoboron compounds.

Crystal and molecular structures of spiro-3,4′-R-(3,3-dideoxy-1,2:5,6-di-O-isopropylidene-α-D-ribo-hexafuranose)-3′-S(and 3′-R)-acetamido-2′-pyrrolidone

1977 ◽  
Vol 55 (9) ◽  
pp. 1454-1462 ◽  
Author(s):  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Hydrogen Bonds ◽  
Least Squares ◽  
Crystal Structures ◽  
Title Compound ◽  
Direct Methods ◽  
Molecular Structures ◽  
Full Matrix ◽  
Space Group ◽  
Crystal And Molecular Structures

Crystals of the 3′-S isomer of the title compound are orthorhombic, a = 23.004(5), b = 11.103(1), c = 7.616(3) Å, Z = 4, space group P212121. Crystals of the 3′-R isomer are orthorhombic, a = 24.898(1), b = 10.4122(4), c = 7.6467(6) Å, Z = 4, space group P212121. The structures were solved by direct methods and were refined by full-matrix least squares procedures to final R values of 0.038 for 1466 and 1996 reflections with I ≥ 3σ(I) for the 3′-S and 3′-R isomers respectively. Both crystal structures consist of discrete molecules linked by systems of intermolecular N—H … O hydrogen bonds and possible weak C—H … O interactions.

Studies in aryltin chemistry. Part 6. Crystal and molecular structures of tetra(p-methylsulphonylphenyl)tin(IV) and tetra(p-methylsulphinylphenyl)tin(IV) monohydrate

1990 ◽  
Vol 68 (8) ◽  
pp. 1277-1282 ◽  
Author(s):  
Ivor Wharf ◽  
Michel G. Simard ◽  
Henry Lamparski
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Direct Method ◽  
Molecular Structures ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Molecular Symmetry ◽  
Asymmetric Unit ◽  
Full Matrix ◽  
Space Group

Tetrakis(p-methylsulphonylphenyl)tin(IV) and tetrakis(p-methylsulphinylphenyl)tin(IV) n-hydrate have been prepared and their spectra (ir 1350–400 cm−1; nmr, 1H, 13C, 119Sn) and X-ray crystal structures are reported. The first compound is monoclinic, space group C2/c, Z = 4, with a = 21.589(6), b = 6.207(3), c = 22.861(11) Å, β = 93.80(3)° (22 °C); the structure was solved by the direct method and refined by full-matrix least squares calculations to R = 0.043 for 2755 observed reflections. It has 2 molecular symmetry with the methyl group and one oxygen atom completely disordered in both CH3S(O2) groups in the asymmetric unit. The second compound is tetragonal, space group P42/n, Z = 2, with a = b = 15.408(6), c = 6.379(2) Å (−100 °C); the structure was solved by the Patterson method and refined by full-matrix least squares calculations to R = 0.060 for 1209 observed reflections. It has [Formula: see text] molecular symmetry with the whole asymmetric unit disordered. Water molecules occupy positions on parallel 42 axes but molecular packing requirements prevent all sites having 100% occupancy giving n ~ 1 for the hydrate. Keywords: Tetra-aryltins, crystal structures, sulphone, sulphoxide, hydrogen-bonding.

Structural studies of organoboron compounds. XX.(Salicylaldoximato-O,N)diphenylboron

1984 ◽  
Vol 62 (7) ◽  
pp. 1363-1368 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Hydrogen Bonds ◽  
Least Squares ◽  
Chelate Ring ◽  
Direct Methods ◽  
Structural Studies ◽  
Organoboron Compounds ◽  
Full Matrix ◽  
Space Group ◽  
Bond Lengths ◽  
Phenolic Oxygen

Crystals of (salicylaldoximato-O,N)diphenylboron are triclinic, a = 10.125(2), b = 10.797(1), c = 14.760(2) Å, α = 89.05(1), β = 86.98(1), γ = 83.18(1)°, Z = 4, space group [Formula: see text]. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.040 and Rw = 0.048 for4145 reflections with I ≥ 3σ(I). The structure consists of two crystallographically independent, but essentially identical, molecules linked by strong [Formula: see text] hydrogen bonds to form continuous spirals along the a axis. The Ph2B moiety is chelated by the phenolic oxygen and oxime nitrogen atoms of the ligand resulting in the formation of a non-planar six-membered chelate ring. Important libration-corrected mean bond lengths are O—B = 1.516(1), N—B = 1.609(2), and C—B = 1.613(2) Å.

Crystal and molecular structure of 2,6-dimethyl-3,5-di[N-methyl]carbamoyl-4-[3,4-methoxy]phenyl-l,4-dihydropyridine hemihydrate and 2,6-dimethyl-3,5-di[N-methyl]carbamoyl-4-[furan]1,4-dihydropyridine

1999 ◽  
Vol 214 (12) ◽  
Author(s):  
M. Bidya Sagar ◽  
K. Ravikumar ◽  
Y. S. Sadanandam
Keyword(s):  
Molecular Structure ◽  
Least Squares ◽  
Crystal Structures ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Asymmetric Unit ◽  
Full Matrix

AbstractThe crystal structures of two dihydropyridines were solved by direct methods and refined by full-matrix least-squares procedure. 2,6-Dimethyl-3,5-di[N-methyl]-carbamoyl-4-[3,4-methoxy]phenyl-1,4-dihydropyridine hemihydrate, CBoth compounds crystallize with two molecules in the asymmetric unit. In compound

Crystal structures of optically active naphthidine (4,4′-diamino-1,1′-binaphthyl) and 1,1′-binaphthyl

1983 ◽  
Vol 61 (1) ◽  
pp. 69-71 ◽  
Author(s):  
Richard A. Pauptit ◽  
James Trotter
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Direct Methods ◽  
Optically Active ◽  
Dihedral Angles ◽  
Full Matrix ◽  
Bond Lengths ◽  
Least Squares Techniques

Crystals of optically active naphthidine and of binaphthyl are tetragonal, P41212 (or P43212), a = 7.945(1), 7.164(2), c = 24.264(5), 27.70(1) Å, respectively, Z = 4. The structures were solved by direct methods and refined by full-matrix least-squares techniques to respective R = 0.068 and 0.030 for 548 and 562 reflexions. The dihedral angles between the planes of the naphthalene residues are 87 and 102°, respectively. Bond lengths and angles are normal.

Reaction of N,N′-dihydroxy-.N,N′-dimethylmethanediamine with phenylboronic acid and the crystal and molecular structure of N,N′-dihydroxy-N,N′-dimethylmethanediamine

1989 ◽  
Vol 67 (11) ◽  
pp. 1959-1963 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Least Squares ◽  
Crystal And Molecular Structure ◽  
Phenylboronic Acid ◽  
Direct Methods ◽  
Exact Formula ◽  
Full Matrix ◽  
Space Group ◽  
Hydrogen Bonded

The reaction of N,N′-dihydroxy-N,N′-dimethylmethanediamine with phenylboronic acid leads to the product 1,7-dimethyl-3,5-diphenyl-2,4,6-trioxa-7-aza-1-azonia-3-bora-5-boratabicyclo[3.3.0]octane rather than the expected product 1,5-dimethyl-3-phenyl-1,5-diaza-2,4-dioxa-3-boracyclohexane. The structure of N,N′-dihydroxy-N,N′-dimethylmethanediamine has been determined and is discussed in terms of its reaction with PhB(OH)2. Crystals of N,N′-dihydroxy-N,N′-dimethylmethanediamine are tetragonal, a = 8.5346(3), c = 8.4178(7) Å, Z = 4, space group P421c. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to a final R of 0.036 and Rw of 0.038 for 333 reflections with I ≥ 3σ(I). The structure consists of hydrogen-bonded dimers having exact [Formula: see text] symmetry. Keywords: N,N′-dihydroxy-N,N′-dimethylmethanediamine, crystal structure.

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