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James Trotter - One of the best experts on this subject based on the ideXlab platform.
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Structural studies of Organoboron Compounds LXIV. Boron chelate formation with glycolohydroxamic acids, and the crystal and molecular structure of 5-(1-hydroxycyclohexyl)-2,2-diphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentane
Canadian Journal of Chemistry, 1996Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ute Schumacher, James TrotterAbstract:The syntheses of representative diphenyl- and difluoroboron chelates of 2-hydroxycarbohydroxamic acids (glycolohydroxamic acids) are reported. Crystals of 5-(1-hydroxycyclohexyl)-2,2-diphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene, 2a, are triclinic, a = 11.5717(5), b = 11.7262(4), c = 14.3529(5) A, α = 90.277(6)°, β = 110.497(5)°, γ = 96.814(5)°, Z = 4, space group The structure was solved by direct methods and refined by full-matrix least-squares procedures to R = 0.042 and Rw = 0.056 for 5318 reflections with I ≥ 3σ(F2). Compound 2a is the first N-unsubstituted hydroxamatoborate derivative to be structurally characterized by an X-ray crystallographic analysis. The solid state structure of 2a consists of centrosymmetric, hydrogen-bonded tetrameric units that also feature intermolecular (aromatic) interactions. Bond lengths include: B—O(N) = 1.557(2) and 1.553(2) A, B—O(N) = 1.558(2) and 1.566(2),A B—C(phenyl) = 1.592(3)–1.601(3) A. Key words: hydroxamatoborate, Organoboron Compound, crystal structure.
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Structural studies of Organoboron Compounds. XLIX, 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The preparation of N,N′-bis(1-phenyl-2-nitroethyl)-N,N′-dihydroxymethanediamine and its subsequent reaction with 4-methoxyphenylboronicacid to yield 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane are described. Crystals of the latter Compound are monoclinic, a = 8.4790(8), b = 16.2100(9), c = 9.4367(6) A, β = 109.342(5)°, Z = 2, space groupP21. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.032 and Rw = 0.039 for 1749 reflections with I ≥ 3σ(I). The molecule has a six-membered BONCNO cycloboronate structure. Bond lengths involving the trigonal planar boron atom are (N)O—B = 1.362(4) and 1.364(5), (aryl)C—B = 1.548(4) A. Key words: Organoboron Compound, crystal structure, cycloboronate, methanediamine.
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Structural studies of Organoboron Compounds XLVIII. 1,4-Diphenyl-3,3:6,6-bis(tetramethylene)-2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ulf Riebe, James TrotterAbstract:The reaction of N-hydroxypyrrolidine with either oxybis(diphenylborane) or phenylboronic acid gives 1,4-diphenyl-3,3:6,6-bis(tetramethylene)-2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane in moderate yield. Crystals of the product are orthorhombic, a = 10.984(2), b = 14.619(2), c = 12.311(2) Å, Z = 4, space group Pccn. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.039 and Rw = 0.043 for 908 reflections with I ≥ 3σ(I). This is the first heterocyclic [2.2.1]heptane system containing a six-membered BONBON ring and a B—O—B bridge to be structurally characterized. The molecule has exact C2 symmetry with the twofold axis passing through the bridging oxygen atom. Bond lengths involving the tetrahedrally coordinated boron atom are B—O(B) = 1.423(3), B—O(N) = 1.497(3), B—N = 1.703(3), and B—C(phenyl) = 1.577(4) Å. Key words: 2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane ring system, crystal structure, Organoboron Compound.
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Structural studies of Organoboron Compounds. XLIII. 4-[(1-Hydroxycyclohexyl)methyl]-2,2,5-triphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ute Schumacher, Mahmood Tajerbashi, James TrotterAbstract:The reaction of N′-hydroxy-N-[(1-hydroxycyclohexyl)methyl]benzamide and diphenylborinic anhydride gives 4-[(1-hydroxycyclohexyl)methyl]-2,2,5-triphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene in nearly quantitative yield. Crystals of the product are monoclinic, a = 9.9117(6), b = 13.308(1), c = 17.339(2) Ǻ, β = 99.420(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 = 0.040 and Rw = 0.047 for 2423 reflections with I > 3σ(I). The molecule has a normal five-membered hydroxamic acid chelate structure, the BONCO ring having a B-envelope conformation. Bond lengths (corrected for libration) (N)O—B = 1.535(3), (C)O—B = 1.569(3), C—B = 1.603(3) and 1.601(3) Ǻ are normal for this type of complex. Key words: Organoboron Compound, boron Compound, crystal structure.
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STRUCTURAL STUDIES OF Organoboron CompoundS. XLII, 4,6-BIS(1-CYANO-1-METHYLETHYL)-2-MESITYL-1,3-DIOXA-4,6-DIAZA-2-BORACYCLOHEXANE
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The condensation of N,N′-bis(1-cyano-1-methylethyl)-N,N′-dihydroxymethanediamine and mesitylboronic acid gives 4,6-bis(1-cyano-1-methylethyl)-2-mesityl-1,3-dioxa-4,6-diaza-2-boracyclohexane in good yield. Crystals of the latter Compound are orthorhombic, a = 15.825(1), b = 17.958(1), c = 14.014(1) Ǻ, Z = 8, space group Pbca. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.037 and Rw = 0.051 for 2844 reflections with 1 ≥ 3σ(I). The molecule has a six-membered cycloboronate structure featuring the first structurally characterized BONCNO ring. The ring was found to have a C-envelope conformation in the solid state. Bond lengths include: O—B(sp2) = 1.356(2) and 1.370(2), and C(aryl)—B = 1.560(2) Ǻ. Key words: Organoboron Compound, boron Compound, crystal structure.
Wolfgang Kliegel - One of the best experts on this subject based on the ideXlab platform.
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Structural studies of Organoboron Compounds LXIV. Boron chelate formation with glycolohydroxamic acids, and the crystal and molecular structure of 5-(1-hydroxycyclohexyl)-2,2-diphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentane
Canadian Journal of Chemistry, 1996Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ute Schumacher, James TrotterAbstract:The syntheses of representative diphenyl- and difluoroboron chelates of 2-hydroxycarbohydroxamic acids (glycolohydroxamic acids) are reported. Crystals of 5-(1-hydroxycyclohexyl)-2,2-diphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene, 2a, are triclinic, a = 11.5717(5), b = 11.7262(4), c = 14.3529(5) A, α = 90.277(6)°, β = 110.497(5)°, γ = 96.814(5)°, Z = 4, space group The structure was solved by direct methods and refined by full-matrix least-squares procedures to R = 0.042 and Rw = 0.056 for 5318 reflections with I ≥ 3σ(F2). Compound 2a is the first N-unsubstituted hydroxamatoborate derivative to be structurally characterized by an X-ray crystallographic analysis. The solid state structure of 2a consists of centrosymmetric, hydrogen-bonded tetrameric units that also feature intermolecular (aromatic) interactions. Bond lengths include: B—O(N) = 1.557(2) and 1.553(2) A, B—O(N) = 1.558(2) and 1.566(2),A B—C(phenyl) = 1.592(3)–1.601(3) A. Key words: hydroxamatoborate, Organoboron Compound, crystal structure.
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Structural studies of Organoboron Compounds. XLIX, 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The preparation of N,N′-bis(1-phenyl-2-nitroethyl)-N,N′-dihydroxymethanediamine and its subsequent reaction with 4-methoxyphenylboronicacid to yield 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane are described. Crystals of the latter Compound are monoclinic, a = 8.4790(8), b = 16.2100(9), c = 9.4367(6) A, β = 109.342(5)°, Z = 2, space groupP21. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.032 and Rw = 0.039 for 1749 reflections with I ≥ 3σ(I). The molecule has a six-membered BONCNO cycloboronate structure. Bond lengths involving the trigonal planar boron atom are (N)O—B = 1.362(4) and 1.364(5), (aryl)C—B = 1.548(4) A. Key words: Organoboron Compound, crystal structure, cycloboronate, methanediamine.
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Structural studies of Organoboron Compounds XLVIII. 1,4-Diphenyl-3,3:6,6-bis(tetramethylene)-2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ulf Riebe, James TrotterAbstract:The reaction of N-hydroxypyrrolidine with either oxybis(diphenylborane) or phenylboronic acid gives 1,4-diphenyl-3,3:6,6-bis(tetramethylene)-2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane in moderate yield. Crystals of the product are orthorhombic, a = 10.984(2), b = 14.619(2), c = 12.311(2) Å, Z = 4, space group Pccn. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.039 and Rw = 0.043 for 908 reflections with I ≥ 3σ(I). This is the first heterocyclic [2.2.1]heptane system containing a six-membered BONBON ring and a B—O—B bridge to be structurally characterized. The molecule has exact C2 symmetry with the twofold axis passing through the bridging oxygen atom. Bond lengths involving the tetrahedrally coordinated boron atom are B—O(B) = 1.423(3), B—O(N) = 1.497(3), B—N = 1.703(3), and B—C(phenyl) = 1.577(4) Å. Key words: 2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane ring system, crystal structure, Organoboron Compound.
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Structural studies of Organoboron Compounds. XLIII. 4-[(1-Hydroxycyclohexyl)methyl]-2,2,5-triphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ute Schumacher, Mahmood Tajerbashi, James TrotterAbstract:The reaction of N′-hydroxy-N-[(1-hydroxycyclohexyl)methyl]benzamide and diphenylborinic anhydride gives 4-[(1-hydroxycyclohexyl)methyl]-2,2,5-triphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene in nearly quantitative yield. Crystals of the product are monoclinic, a = 9.9117(6), b = 13.308(1), c = 17.339(2) Ǻ, β = 99.420(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 = 0.040 and Rw = 0.047 for 2423 reflections with I > 3σ(I). The molecule has a normal five-membered hydroxamic acid chelate structure, the BONCO ring having a B-envelope conformation. Bond lengths (corrected for libration) (N)O—B = 1.535(3), (C)O—B = 1.569(3), C—B = 1.603(3) and 1.601(3) Ǻ are normal for this type of complex. Key words: Organoboron Compound, boron Compound, crystal structure.
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STRUCTURAL STUDIES OF Organoboron CompoundS. XLII, 4,6-BIS(1-CYANO-1-METHYLETHYL)-2-MESITYL-1,3-DIOXA-4,6-DIAZA-2-BORACYCLOHEXANE
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The condensation of N,N′-bis(1-cyano-1-methylethyl)-N,N′-dihydroxymethanediamine and mesitylboronic acid gives 4,6-bis(1-cyano-1-methylethyl)-2-mesityl-1,3-dioxa-4,6-diaza-2-boracyclohexane in good yield. Crystals of the latter Compound are orthorhombic, a = 15.825(1), b = 17.958(1), c = 14.014(1) Ǻ, Z = 8, space group Pbca. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.037 and Rw = 0.051 for 2844 reflections with 1 ≥ 3σ(I). The molecule has a six-membered cycloboronate structure featuring the first structurally characterized BONCNO ring. The ring was found to have a C-envelope conformation in the solid state. Bond lengths include: O—B(sp2) = 1.356(2) and 1.370(2), and C(aryl)—B = 1.560(2) Ǻ. Key words: Organoboron Compound, boron Compound, crystal structure.
Steven J. Rettig - One of the best experts on this subject based on the ideXlab platform.
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Structural studies of Organoboron Compounds LXIV. Boron chelate formation with glycolohydroxamic acids, and the crystal and molecular structure of 5-(1-hydroxycyclohexyl)-2,2-diphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentane
Canadian Journal of Chemistry, 1996Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ute Schumacher, James TrotterAbstract:The syntheses of representative diphenyl- and difluoroboron chelates of 2-hydroxycarbohydroxamic acids (glycolohydroxamic acids) are reported. Crystals of 5-(1-hydroxycyclohexyl)-2,2-diphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene, 2a, are triclinic, a = 11.5717(5), b = 11.7262(4), c = 14.3529(5) A, α = 90.277(6)°, β = 110.497(5)°, γ = 96.814(5)°, Z = 4, space group The structure was solved by direct methods and refined by full-matrix least-squares procedures to R = 0.042 and Rw = 0.056 for 5318 reflections with I ≥ 3σ(F2). Compound 2a is the first N-unsubstituted hydroxamatoborate derivative to be structurally characterized by an X-ray crystallographic analysis. The solid state structure of 2a consists of centrosymmetric, hydrogen-bonded tetrameric units that also feature intermolecular (aromatic) interactions. Bond lengths include: B—O(N) = 1.557(2) and 1.553(2) A, B—O(N) = 1.558(2) and 1.566(2),A B—C(phenyl) = 1.592(3)–1.601(3) A. Key words: hydroxamatoborate, Organoboron Compound, crystal structure.
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Structural studies of Organoboron Compounds. XLIX, 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The preparation of N,N′-bis(1-phenyl-2-nitroethyl)-N,N′-dihydroxymethanediamine and its subsequent reaction with 4-methoxyphenylboronicacid to yield 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane are described. Crystals of the latter Compound are monoclinic, a = 8.4790(8), b = 16.2100(9), c = 9.4367(6) A, β = 109.342(5)°, Z = 2, space groupP21. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.032 and Rw = 0.039 for 1749 reflections with I ≥ 3σ(I). The molecule has a six-membered BONCNO cycloboronate structure. Bond lengths involving the trigonal planar boron atom are (N)O—B = 1.362(4) and 1.364(5), (aryl)C—B = 1.548(4) A. Key words: Organoboron Compound, crystal structure, cycloboronate, methanediamine.
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Structural studies of Organoboron Compounds XLVIII. 1,4-Diphenyl-3,3:6,6-bis(tetramethylene)-2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ulf Riebe, James TrotterAbstract:The reaction of N-hydroxypyrrolidine with either oxybis(diphenylborane) or phenylboronic acid gives 1,4-diphenyl-3,3:6,6-bis(tetramethylene)-2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane in moderate yield. Crystals of the product are orthorhombic, a = 10.984(2), b = 14.619(2), c = 12.311(2) Å, Z = 4, space group Pccn. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.039 and Rw = 0.043 for 908 reflections with I ≥ 3σ(I). This is the first heterocyclic [2.2.1]heptane system containing a six-membered BONBON ring and a B—O—B bridge to be structurally characterized. The molecule has exact C2 symmetry with the twofold axis passing through the bridging oxygen atom. Bond lengths involving the tetrahedrally coordinated boron atom are B—O(B) = 1.423(3), B—O(N) = 1.497(3), B—N = 1.703(3), and B—C(phenyl) = 1.577(4) Å. Key words: 2,5,7-trioxa-3,6-diazonia-1,4-diboratabicyclo[2.2.1]heptane ring system, crystal structure, Organoboron Compound.
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Structural studies of Organoboron Compounds. XLIII. 4-[(1-Hydroxycyclohexyl)methyl]-2,2,5-triphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Ute Schumacher, Mahmood Tajerbashi, James TrotterAbstract:The reaction of N′-hydroxy-N-[(1-hydroxycyclohexyl)methyl]benzamide and diphenylborinic anhydride gives 4-[(1-hydroxycyclohexyl)methyl]-2,2,5-triphenyl-1,3-dioxa-4-azonia-2-borata-4-cyclopentene in nearly quantitative yield. Crystals of the product are monoclinic, a = 9.9117(6), b = 13.308(1), c = 17.339(2) Ǻ, β = 99.420(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 = 0.040 and Rw = 0.047 for 2423 reflections with I > 3σ(I). The molecule has a normal five-membered hydroxamic acid chelate structure, the BONCO ring having a B-envelope conformation. Bond lengths (corrected for libration) (N)O—B = 1.535(3), (C)O—B = 1.569(3), C—B = 1.603(3) and 1.601(3) Ǻ are normal for this type of complex. Key words: Organoboron Compound, boron Compound, crystal structure.
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STRUCTURAL STUDIES OF Organoboron CompoundS. XLII, 4,6-BIS(1-CYANO-1-METHYLETHYL)-2-MESITYL-1,3-DIOXA-4,6-DIAZA-2-BORACYCLOHEXANE
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The condensation of N,N′-bis(1-cyano-1-methylethyl)-N,N′-dihydroxymethanediamine and mesitylboronic acid gives 4,6-bis(1-cyano-1-methylethyl)-2-mesityl-1,3-dioxa-4,6-diaza-2-boracyclohexane in good yield. Crystals of the latter Compound are orthorhombic, a = 15.825(1), b = 17.958(1), c = 14.014(1) Ǻ, Z = 8, space group Pbca. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.037 and Rw = 0.051 for 2844 reflections with 1 ≥ 3σ(I). The molecule has a six-membered cycloboronate structure featuring the first structurally characterized BONCNO ring. The ring was found to have a C-envelope conformation in the solid state. Bond lengths include: O—B(sp2) = 1.356(2) and 1.370(2), and C(aryl)—B = 1.560(2) Ǻ. Key words: Organoboron Compound, boron Compound, crystal structure.
Guozhong Li - One of the best experts on this subject based on the ideXlab platform.
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the synthesis photophysical properties and fluoride anion recognition of a novel branched Organoboron Compound
Dyes and Pigments, 2009Co-Authors: Guohui Zhang, Guozhong LiAbstract:A novel two-branched Organoboron Compound, N,N-bis(7-dimesitylboryl-9,9-diethyl-9H-fluorene-2-yl)aniline, containing a phenylamino group as a π-electron donor, fluorene groups as π-bridges and dimesitylboryl groups as electron acceptors, was synthesized and its photophysical properties in various solvents as well as its fluoride anion recognition properties were investigated. The synthesised Compound exhibited strong fluorescence in all solvents with the fluorescence changing from blue to orange on going from solvents of low polarity to those of high polarity. The Compound was able to recognize fluoride anions in high sensitivity owing to strong interactions between boron atoms and fluoride anions.
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a trivalent Organoboron Compound as one and two photon fluorescent chemosensor for fluoride anion
Sensors and Actuators B-chemical, 2008Co-Authors: Guozhong LiAbstract:Abstract The photophysical properties of a fluorene derivative with three coordinated boron and nitrogen as electron acceptor and donor group, respectively, were studied. The bonding of this Compound with fluoride anion was exactly examined by linear absorption and single and two-photon-excited fluorescence technique. This Compound is shown to be a two-photon fluorescent sensor for fluoride anion with high sensitivity and selectivity, which can be mainly attributed to the B–F interaction.
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synthesis and blue violet two photon excited fluorescence of a new Organoboron Compound
Journal of Molecular Structure, 2008Co-Authors: Guozhong Li, Guohui ZhangAbstract:A new A-π-D-π-A type Organoboron Compound, 3,6-bis(dimesitylboryl)-N-butyl-carbazole (abbreviated as BBC), with trivalent boron as electron acceptor and carbazole as electron donor and π-conjugated core, has been synthesized and its single and two-photon related photophysical properties experimentally investigated. Pumped by 720 nm laser pulses in femtosecond regime, it showed strong two-photon excited blue-violet fluorescence at 393 nm in toluene and 403 nm in THF. The measured two-photon absorption cross-section by two-photon fluorescence method in toluene and THF is 34 GM and 38 GM, respectively.
Gottfried Lubkowitz - One of the best experts on this subject based on the ideXlab platform.
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Structural studies of Organoboron Compounds. XLIX, 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The preparation of N,N′-bis(1-phenyl-2-nitroethyl)-N,N′-dihydroxymethanediamine and its subsequent reaction with 4-methoxyphenylboronicacid to yield 4,6-bis(1-phenyl-2-nitroethyl)-2-(4-methoxyphenyl)-1,3-dioxa-4,6-diaza-2-boracyclohexane are described. Crystals of the latter Compound are monoclinic, a = 8.4790(8), b = 16.2100(9), c = 9.4367(6) A, β = 109.342(5)°, Z = 2, space groupP21. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.032 and Rw = 0.039 for 1749 reflections with I ≥ 3σ(I). The molecule has a six-membered BONCNO cycloboronate structure. Bond lengths involving the trigonal planar boron atom are (N)O—B = 1.362(4) and 1.364(5), (aryl)C—B = 1.548(4) A. Key words: Organoboron Compound, crystal structure, cycloboronate, methanediamine.
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STRUCTURAL STUDIES OF Organoboron CompoundS. XLII, 4,6-BIS(1-CYANO-1-METHYLETHYL)-2-MESITYL-1,3-DIOXA-4,6-DIAZA-2-BORACYCLOHEXANE
Canadian Journal of Chemistry, 1991Co-Authors: Wolfgang Kliegel, Steven J. Rettig, Gottfried Lubkowitz, James TrotterAbstract:The condensation of N,N′-bis(1-cyano-1-methylethyl)-N,N′-dihydroxymethanediamine and mesitylboronic acid gives 4,6-bis(1-cyano-1-methylethyl)-2-mesityl-1,3-dioxa-4,6-diaza-2-boracyclohexane in good yield. Crystals of the latter Compound are orthorhombic, a = 15.825(1), b = 17.958(1), c = 14.014(1) Ǻ, Z = 8, space group Pbca. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.037 and Rw = 0.051 for 2844 reflections with 1 ≥ 3σ(I). The molecule has a six-membered cycloboronate structure featuring the first structurally characterized BONCNO ring. The ring was found to have a C-envelope conformation in the solid state. Bond lengths include: O—B(sp2) = 1.356(2) and 1.370(2), and C(aryl)—B = 1.560(2) Ǻ. Key words: Organoboron Compound, boron Compound, crystal structure.