Structural studies of organoboron compounds. XVII. Preparation and crystal and molecular structure of 3a-methyl-2,4,9a-triphenyl-1,2,3a,4,9,9a-hexahydro-1,3,9-trioxa-3a-azonia-2-bora-9a-boratacyclopenta[b]naphthalene

1984 ◽  
Vol 62 (5) ◽  
pp. 845-855 ◽  
Author(s):  
W. Kliegel ◽  
D. Nanninga ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Least Squares ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Phenylboronic Acid ◽  
Phenyl Group ◽  
Direct Methods ◽  
Addition Product ◽  
Structural Studies ◽  
Full Matrix

The title compound was prepared by the reaction of 8-methyl-6,6-diphenyl-5,7-dioxa-8-azonia-6-borata-6,7-dihydro-5H-benzocycloheptene (1) with phenylboronic acid. Crystals of 3a-methyl-2,4,9a-triphenyl-1,2,3a,4,9,9a-hexahydro-1,3,9-trioxa-3a-azonia-2-bora-9a-boratacyclopenta[b]naphthalene are monoclinic, a = 11.8548(4), b = 22.7837(4), c = 8.5457(3) Å, β = 106.952(2)°, Z = 4, space group P21/n. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.040 and Rw = 0.047 for 2970 reflections with I ≥ 3σ(I). The molecule was found to be a formal addition product between 1 and PhBO which had undergone a 1,4-shift of a phenyl group from boron to carbon. The backbone of the molecule consists of a folded system of three fused rings. The structure contains the longest known B(sp3)—N(sp3) bond, 1.759(2) Å.

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.

Structural studies of organoboron compounds. LIII. N,N-Diethylhydroxylamine-(O-B)1,7-dimethyl-3,5-diphenyl-2,4,6-trioxa-7-aza-1-azonia-3-bora-5- boratabicyclo[3.3.0]octane

1992 ◽  
Vol 70 (7) ◽  
pp. 2022-2026 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Gottfried Lubkowitz ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Hydrogen Bond ◽  
Least Squares ◽  
Title Compound ◽  
Condensation Product ◽  
Phenylboronic Acid ◽  
Direct Methods ◽  
High Yield ◽  
Structural Studies ◽  
Full Matrix ◽  
Bond Lengths

Reaction of the condensation product of N,N′-dimethyl-N,N′-dihydroxymethanediamine and phenylboronic acid with N,N-diethylhydroxylamine gives N,N-diethylhydroxylamine(O-B)1,7-dimethyl-3,5-diphenyl-2,4,6-trioxa-7-aza-1-azonia-3-bora-5-boratabicyclo[3.3.0]octane [3-(2-ethyl-1-oxa-2-azoniabutyl)-1,7-dimethyl-3,5-diphenyl-2,4,6-trioxa-7-aza-1-azonia-3,5-diboratabicyclo[3.3.0]octane, 3] in high yield. Crystals of 3 are orthorhombic, a = 11.8132(11), b = 15.4768(11), c = 11.7325(16) Å, Z = 4, space group P212121. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.039 and Rw = 0.044 for 1729 reflections with I ≥ 2σ(I). The title compound is the second example of this recently characterized class of O-B coordinated hydroxylamine complexes, stabilized by an intramolecular [Formula: see text] hydrogen bond [Formula: see text]. Bond lengths about boron are: B—O(N) = 1.482(4)–1.526(4), B—O(B) = 1.412(4) and 1.420(4), B—N = 1.712(4), B—C = 1.591(5) and 1.602(5) Å.

Structural studies of organoboron compounds. LX. Reaction of sterically hindered arylboronic acids with 2-(hydroxyamino)alkanols. Crystal and molecular structure of 2-mesityl-6,6-pentamethylene-1,3-dioxa-4-aza-2-boracyclohexane

1994 ◽  
Vol 72 (4) ◽  
pp. 1154-1161 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Gottfried Lubkowitz ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Least Squares ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Structural Studies ◽  
Full Matrix ◽  
Space Group ◽  
X Ray ◽  
Arylboronic Acids ◽  
Sterically Hindered

Three 2-(hydroxyamino)alkanols have been reacted with sterically hindered arylboronic acids, ArB(OH)2. When Ar = o-tolyl, 1:2 condensates having bicyclic structures are formed but when Ar = mesityl (2,4,6-(CH3)3C6H2), 1:1 condensates having six-membered cycloboronate structures result. These 1:1 condensates represent the first examples of N-unsubstituted 1,3-dioxa-4-aza-2-boracyclohexane derivatives. An X-ray analysis of one example provides unambiguous proof of the structure. Crystals of 2-mesityl-6,6-pentamethylene-1,3-dioxa-4-aza-2-boracyclohexane, 3c, are monoclinic, a = 11.076(9), b = 23.94(2), c = 13.414(9) Å, β = 109.40(5)°, Z = 8, space group P21/n. The structure was solved by direct methods and refined by full-matrix least-squares procedures to R = 0.051 and Rw = 0.058 for 2037 reflections with I ≥ 3σ(F2).

Structural studies of organoboron compounds. XXXIX.1 1,4-Bis(2,2-diethoxyethyl)-6,8-diphenyl-5,7,9-trioxa-4-aza-1-azonia-8- bora-6-boratabicyclo[4.3.0]nonane

1990 ◽  
Vol 68 (10) ◽  
pp. 1791-1796 ◽  
Author(s):  
Henning Amt ◽  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Title Compound ◽  
Phenylboronic Acid ◽  
Direct Methods ◽  
Organoboron Compound ◽  
Structural Studies ◽  
Full Matrix ◽  
Space Group ◽  
Bond Lengths

Reaction of N,N′-1,2-ethanediylidenebis(2,2-diethoxyethanamine)- N,N′-dioxide and phenylboronic acid yields the title compound. Crystals of 1,4-bis(2,2-diethoxyethyl)-6,8-diphenyl-5,7,9-trioxa-4-aza-1-azonia-8-bora-6-boratabicyclo[4.3.0]-nonane are triclinic, a = 12.625(2), b = 13.962(2), c = 9.273(1) Å, α = 104.81(1), β = 98.61(1), γ = 106.52(1)°, Z = 2, space group [Formula: see text]. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.058 and Rw = 0.081 for 3677 reflections with I ≥ 3σ(I). The molecule has a bicyclo[4.3.0]nonane structure containing one transannular N—B bond. Important bond lengths are sp3-bomn, N—B = 1.759(3), O—B = 1.435(3) and 1.454(3), C—B = 1.579(4); sp2-boron, O—B = 1.335(3) and 1.404(3), C—B = 1.557(4) Å. The (sp3)B—C(phenyl) bond is the shortest yet reported for this type of compound.Keywords: crystal structure, boron compound, organoboron compound.

Crystal and Molecular Structure of Hexakis(dimethylamino)cyclotriphosphazene, [NP(NMe2)2]3

1973 ◽  
Vol 51 (8) ◽  
pp. 1295-1302 ◽  
Author(s):  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Least Squares ◽  
Electron Density ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Full Matrix ◽  
Space Group ◽  
The Mean

Crystals of the title compound are monoclinic, a = 15.539(4), b = 9.061(1), c = 16.707(6) Å, β = 107.19(5)°, Z = 4, space group P21/c. The measured and calculated densities are 1.19 and 1.180(1) g cm−3, respectively. The structure was determined by direct methods and refined by electron-density and full-matrix least-squares procedures to R = 0.047 for 2503 observed reflections. The six-membered phosphazene ring is slightly, but significantly, non-planar, the conformation being that of a distorted boat. The molecule has approximate D3 symmetry. The ring P—N bonds are all equal, mean P—N = 1.588(3) Å, and the relatively short exocyclic P—N bonds, mean 1.652(4) Å, indicate the presence of exocyclic π-bonding in the molecule. The N—C bonds range from 1.417(7) to 1.471(5) with a mean of 1.45(2) Å. The mean endocyclic N—P—N and P—N—P angles are 116.7(4) and 123.0(4)°, respectively, while the exocyclic N—P—N angles average 101.5(8)°.

Structural studies of organoboron compounds LXI. Synthesis of (alkylideniminoxy)- diarylboranes and crystal and molecular structure of dimeric (ethylideniminoxy)-bis(4-methoxyphenyl)borane [3,3,6,6-tetrakis(4-methoxyphenyl)-2,5-diethylidene-1,4-dioxa-2,5-diazonia-3,6-diboratacyclohexane]

1994 ◽  
Vol 72 (7) ◽  
pp. 1735-1740 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Dierk Nanninga ◽  
Ulf Riebe ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Least Squares ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Structural Studies ◽  
Organoboron Compounds ◽  
Full Matrix ◽  
Space Group ◽  
Dimeric Structure

Oxime diarylborinates, 4, were obtained from several aliphatic and aromatic aldoximes as well as from cyclic ketoximes by acylation with a diarylborinic acid or anhydride (R2B-X, R = aryl, X = OH or OBR2). Compounds 4 could also be synthesized by condensation of an (aminoxy)-diarylborane, which supposedly has a cyclodimeric BONBON structure, with an aldehyde or with a ketone. Crystals of 3,3,6,6-tetrakis(4-methoxyphenyl)-2,5-diethylidene-1,4-dioxa-2,5-diazonia-3,6-diboratacyclohexane, 4b, are monoclinic, a = 7.9182(9), b = 19.7582(9), c = 9.6779(8) Å, β = 91.598(8)°, Z = 2, space group P21/n. The structure was solved by direct methods and refined by full-matrix least-squares procedures to R = 0.033 and Rw = 0.034 for 2344 reflections with I ≥ 3σ(F2). A dimeric structure featuring a central six-membered BONBON ring has been established for the oxime diarylborinate 4b. This represents the first structurally characterized example of a monocyclic BONBON ring.

Crystal and Molecular Structure of B,B- Diphenylboroxazolidine (2-Aminoethyl Diphenylborinate),

1973 ◽  
Vol 51 (8) ◽  
pp. 1288-1294 ◽  
Author(s):  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Least Squares ◽  
Electron Density ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Full Matrix ◽  
Bond Lengths

Crystals of the title compound are monoclinic, a = 13.840(1), b = 8.9169(5), c = 10.170(1) Å, β = 98.85(1)°, Z = 4, space group P21/n. The structure was determined by direct methods, and refined by electron-density and full-matrix least-squares procedures to R 0.041 for 1458 observed reflections. The five-membered boroxazolidine ring is in the half-chair conformation. Bond angles in the ring range from 99.7° for OBN to 110.1° for BOC. Bond lengths are as follows: mean B—C, 1.611(2), B—N, 1.653(3), B—O, 1.484(3), C—N, 1.485(3), C—O, 1.413(3), mean C—C (aromatic), 1.383(11), and C—C, 1.505(4) Å. The structure consists of discrete molecules linked by O…H—N hydrogen bonds (2.874(2) Å) to form continuous spirals about the 21 axes.

Structural studies of organoboron compounds. XXXVII. 8,8-Pentamethylene-6-phenyl-6,9-epoxy-5,7-dioxa-8-azonia-6-borata-6,7,8,9-tetrahydro-5H-benzocycloheptene

1990 ◽  
Vol 68 (1) ◽  
pp. 64-68 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Hans-Walter Motzkus ◽  
Klaus Drückler ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Title Compound ◽  
Phenylboronic Acid ◽  
Direct Methods ◽  
Structural Studies ◽  
Boron Compounds ◽  
Full Matrix ◽  
Space Group ◽  
Bond Lengths

Condensation of equimolar amounts of salicylaldehyde, N-hydroxypiperidine, and phenylboronic acid yields the title compound. Crystals of 8,8-pentamethylene-6-phenyl-6,9-epoxy-5,7-dioxa-8-azonia-6-borata-6,7,8,9-tetrahydro-5H-benzocycloheptene are monoclinic, a = 12.773(1), b = 11.9600(7), c = 10.6411(6) Å, β = 103.786(7)°, Z = 4, space group P21/c. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.039 and Rw = 0.047 for 2420 reflections with I ≥ 3σ(I). The compound has a bridged heterocyclic B,N-betaine structure with a PhB(OR)3 anionic centre. Bond lengths (corrected for libration) include: B—O(aryl C) = 1.481(2), B—O(alkyl C) = 1.488(2), B—O(N) = 1.539(2), and B—C = 1.591(2) Å. Keywords: organoboron, boron compounds, crystal structure.

Structural studies of organoboron compounds. XIV. Preparation and crystal and molecular structure of 4-isopropylidene-2,5,5-triphenyl-1,3-dioxa-4-azonia-2-bora-5-boratacyclopentane

1983 ◽  
Vol 61 (10) ◽  
pp. 2329-2333 ◽  
Author(s):  
W. Kliegel ◽  
D. Nanninga ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Physical Properties ◽  
Least Squares ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Structural Studies ◽  
Organoboron Compounds ◽  
Full Matrix ◽  
Space Group ◽  
Tetrahedral Boron

Details of the synthesis, physical properties, and molecular structure of 4-isopropylidene-2,5,5-triphenyl-1,3-dioxa-4-azonia-2-bora-5-boratacyclopentane are reported. Crystals of this compound are monoclinic, a = 14.126(3), b = 16.008(1), c = 8.642(2) Å, β = 99.052(8)°, Z = 4, space group P21/n. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.032 and Rw = 0.033 for 1117 reflections with I ≥ 3σ(I). The molecule contains a nearly planar five-membered B—O—B—O—N ring which incorporates both trigonal planar boron (B—O = 1.333(4) and 418(4), B—C = 1.548(5) Å) and tetrahedral boron atoms (B—O = 1.495(4), B—N = 1.676(4), B—C = 2 at 1.603(5) Å). Other important libration-corrected bond distances include: C=N = 1.284(3) and N—O = 1.418(3) 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

Sign in / Sign up

Export Citation Format

Share Document