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

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.


1990 ◽  
Vol 68 (10) ◽  
pp. 1791-1796 ◽  
Author(s):  
Henning Amt ◽  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter

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.



1990 ◽  
Vol 68 (1) ◽  
pp. 64-68 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Hans-Walter Motzkus ◽  
Klaus Drückler ◽  
Steven J. Rettig ◽  
James Trotter

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.



1988 ◽  
Vol 66 (5) ◽  
pp. 1091-1096 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter

Details of the preparation and structure of the title compound are given. Crystals of 6,6-diethyl-2,2-diphenvl-1,3-dioxa-6-azonia-2-boratacyclooctane monohydrate are orthorhombic, a = 7.0322(2), b = 16.3505(7), c = 16.8164(4) Å, Z = 4, space group P212121. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.045 and Rw = 0.050 for 2013 reflections with I ≥ 3σ(I). The monocyclic eight-membered B, N-betaine is the first to be structurally characterized. The eight-membered chelate ring has a conformation intermediate between the S4 and boat-boat forms which is probably stabilized by transannular [Formula: see text] interactions. The average libration-corrected O—B and B—C bond lengths of 1.500 and 1.639 Å are, respectively, the shortest and longest yet observed for an O,O-chelate of diphenylboron.



1987 ◽  
Vol 65 (3) ◽  
pp. 590-594 ◽  
Author(s):  
Chris Orvig ◽  
Steven J. Rettig ◽  
James Trotter

The reaction of maltol (3-hydroxy-2-methyl-4-pyrone) with diphenylborinic acid affords a high yield of the title compound. Crystals of (maltolato)diphenylboron are monoclinic, a = 14.3481(6), b = 8.3994(3), c = 12.6657(5) Å, β = 100.892(4)°, Z = 4, space group P21/n. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.041 and Rw = 0.052 for 2052 reflections with I ≥ 3σ(1). The molecule contains a five-membered C2O2B ring having a flattened B-envelope conformation, the B atom being displaced 0.081(2) Å from the C2O2 plane. Structural and spectroscopic data are consistent with weak binding of the maltolate oxygen atoms to boron. Bond distances (corrected for libration) are O—B = 1.533(2) and 1.600(3), B—C = 1.600(3) and 1.605(3) Å.



1990 ◽  
Vol 68 (10) ◽  
pp. 1797-1802 ◽  
Author(s):  
Henning Amt ◽  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter

The synthesis of 4,7-dicyclohexyl-2,2,5,6-tetraphenyl-1,3-dioxa-4-aza-7-azonia-2-boratacycloheptane is reported. Crystals of the compound are orthorhombic, a = 10.893(1), b = 28.072(1), c = 10.596(1) Å, Z = 4, space group P212121. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.036 and Rw = 0.043 for 2480 reflections with I ≥ 3σ(I). The molecule has a seven-membered chelate structure. The seven-membered ring, which has a twisted chair conformation, is stabilized by an intramolecular [Formula: see text] hydrogen bond. Bond lengths O—B = 1.468(4) and 1.554(4), C—B = 1.621(5) and 1.626(4) Å are consistent with moderately strong binding of the diphenylboron moiety by the O,O-chelating ligand. Keywords: crystal structure, organoboron compound, boron compound.



1988 ◽  
Vol 66 (5) ◽  
pp. 1117-1122 ◽  
Author(s):  
Henning Amt ◽  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter

Details of the preparation and physical properties of the title compound are given. Crystals of 1,9-dimethyl-3,5,7- triphenyl-2,4,6,8-tetraoxa-1,9-diazonia-5-bora-3,7-diboratatricyclo[5.4.0.03,9]undecane are orthorhombic, a = 9.4026(3), b = 9.4663(2), c = 24.7462(9) Å, Z = 4, space group P212121. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.036 and Rw = 0.038 for 1536 reflections with I ≥ 3σ(I). The three six-membered and two seven-membered rings comprising the tricyclo[5.4.0.03,9]undecane ring system all have boat or boat-like conformations. Important bond lengths (corrected for libration) are: B(sp3)—N = 1.649(6) and 1.668(6), B(sp3)—O(N) = 1.492(5) and 1.497(6), B(sp3)—O[B(sp2)] = 1.444(6) and 1.438(5), B(sp3)—C = 1.600(6) and 1.594(7), B(sp2)—O = 1.357(6) and 1.370(6), B(sp2)—C = 1.574(6) Å.



1984 ◽  
Vol 62 (5) ◽  
pp. 845-855 ◽  
Author(s):  
W. Kliegel ◽  
D. Nanninga ◽  
Steven J. Rettig ◽  
James Trotter

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.



1992 ◽  
Vol 70 (7) ◽  
pp. 2027-2032 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Gottfried Lubkowitz ◽  
Steven J. Rettig ◽  
James Trotter

The synthesis of N1-cyclohexyl-N1,N2-dihydroxy-1-phenyl-1,2-propanediamine and its reaction with phenylboronic acid to produce 4-cyclohexyl-2-methyl-3,6,8-triphenyl-5,7,9-trioxa-4-aza-1-azonia-8-bora-6-boratabicyclo[4.3.0]nonane, 5, in moderate yield are described. Crystals of the organoboron derivative 5 are triclinic, a = 11.4142(8), b = 12.4719(8), c = 10.2154(6) Å, α = 75.177(6), β = 112.306(5), γ = 105.000(6)°, 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 = 0.037 and Rw = 0.053 for 4232 reflections with I ≥ 3σ(I). The bicyclo[4.3.0]nonane system consists of a six-membered BONCNN ring and a five-membered BOBON ring cis-fused about the transannular N→B bond. Bond lengths involving boron are: (sp2)B—O(B) = 1.336(2), (sp2)B—O(N) = 1.411(2), (sp2)B—C(aryl) = 1.557(2), (sp3)B—O(B) = 1.457(2), (sp3)B—O(N) = 1.434(2), (sp3)B—N = 1.706(2), and (sp3)B—C(aryl) = 1.593(2) Å.



1988 ◽  
Vol 66 (8) ◽  
pp. 2007-2013 ◽  
Author(s):  
William R. Cullen ◽  
Steven J. Rettig ◽  
James Trotter ◽  
Eugene B. Wickenheiser

Details of the synthesis and physical properties of the title compound are reported along with a new preparation of 3-benzoyl-(+)-camphor. Crystals of (3-benzoyl-(+)-camphorato)diphenylboron are triclinic, a = 9.0362(3), b = 9.4679(3), c = 14.2731(7) Å, α = 101.920(3), β = 100.086(3), γ = 93.251(3)°, Z = 2, space group P1. The structure was solved by non-routine application of direct methods and was refined by full-matrix least-squares procedures to R = 0.036 and Rw = 0.039 for 4094 reflections with I ≥ 3σ(I). The unit-cell contains two crystallographically independent molecules, related to one another in the crystal lattice by a pseudo-inversion centre, and having the same configuration but different conformations. The structure analysis shows that the chiral, anionic, 1,3-diketonate ligand derived from 3-benzoyl-(+)-camphor is not symmetrically delocalized like most related ligands, resulting in significantly different O—B bond lengths. Bond lengths (corrected for libration) include: O—B = 1.514(4), 1.522(4); 1.568(4) and 1.567(4) Å; C—B = 1.594(5)−1.616(5) Å.



1990 ◽  
Vol 68 (10) ◽  
pp. 1803-1807 ◽  
Author(s):  
Chris Orvig ◽  
Steven J. Rettig ◽  
James Trotter ◽  
Zaihui Zhang

(3-Hydroxy-2-methyl-1-(p-tolyl)-4-pyridinonato)diphenylboron has been prepared in high yield by the reaction of 3-hydroxy-2-methyl-1-(p-tolyl)-4-pyridinone with diphenylborinic acid. Crystals of the hemi-acetone solvate are triclinic, a = 15.119(2), b = 16.528(1), c = 9.5802(9) Å, α = 98.721(6), β = 93.344(8), γ = 102.443(6)°, 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 = 0.050 and Rw = 0.065 for 4330 reflections with I ≥ 3σ(I). The five-membered chelate rings in both of the two crystallographically independent molecules have flattened B-envelope conformations (maximum deviations from the mean planes = 0.114(4) and 0.065(5) Å). Mean bond lengths O—B = 1.553 and C—B = 1.599 Å are consistent with intermediate strength binding of the diphenylboron moiety by the O,O-chelating ligand. Keywords: crystal structure, organoboron compound.



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