Structural studies of dibenz[c,f]azocines. I. N-Methyl-5,6-dihydro-7H,12H-dibenz[c,f]azocine

Hardy, A. D.; Ahmed, F. R.

doi:10.1107/s0567740874005590

Cited by 13 publications

(7 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4 strained rings (Royer, Schievelbein~ Kalyanaraman & Bertrand, 1972;Hussain & Hope, 1969). The average C-N bond length, 1.465(4) compares favorably with the recently reported value of 1.456(2) /k found in 1,3,5,7-tetraceto-1,3,5,7-tetrazacyclooctane (Choi, Abel, Dickens & Stewart, 1973) and the values found in dibenz[c, f]azocines (Hardy & Ahmed, 1974). The C-O bond lengths are also well within the range exhibited by similar bonds (Cox & Jeffrey, 1951;Smith, Fitzgerald, Caughlon, Kerr & Ashore, 1974).…”

Section: C(i)-oo27(s)supporting

confidence: 73%

The crystal and molecular structure of cis-1,5-bis(toluene-p-sulfonyl)-3,7-dihydroxyoctahydro-1,5-diazocine

Clearfield¹,

Jones²,

Kellum³

et al. 1975

Acta Crystallogr Sect B

View full text Add to dashboard Cite

Crystals of cis-l,5-bis(toluene-p-sulfonyl)-3,7-dihydroxyoctahydro-l,5-diazocine are orthorhombic, space group Pbca. The unit-cell constants are a= 12.988 (2), b=21.304 (3) and c= 15.299 (2) A, Z= 8.Three-dimensional intensity data (1797 reflections) were obtained with a CAD-4 automated four-circle diffractometer. The structure was solved by direct methods and refined to a conventional R value of 3.8 %. The eight-membered ring has an extended crown conformation and exhibits strain. The hydroxyl groups are definitely cis, confirming earlier spectroscopic analysis. The toluene-p-sulfonate groups are quite regular and inclined to the mean plane of the eight-membered ring at angles of 161 and 167 °. The molecules are held together by hydrogen bonds along the x direction and by van der Waals forces in the other directions.

show abstract

Section: C(i)-oo27(s)supporting

confidence: 73%

The crystal and molecular structure of cis-1,5-bis(toluene-p-sulfonyl)-3,7-dihydroxyoctahydro-1,5-diazocine

Clearfield¹,

Jones²,

Kellum³

et al. 1975

Acta Crystallogr Sect B

View full text Add to dashboard Cite

show abstract

“…Models indicated that the orientation of the methylene protons at C-12 with respect to each adjacent benzene ring was equivalent to 4 = 90". An X-ray diffraction study on l a where X = H and I d where X = Br revealed that, in the solid, both molecules exist in a boat-chair conformation with the N-methyl group in a pseudo-axial position (13). The angles 4 for l a and I d were found to be 87.5 + 0.3" and 86.9 + 1.2" (14), respectively.…”

Section: Figmentioning

confidence: 99%

The effect of substituents on geminal proton–proton coupling constants. III

Renaud¹,

Bovenkamp²,

Fraser³

et al. 1977

Can. J. Chem.

View full text Add to dashboard Cite

RAJ CAPOOR. Can. J. Chem. 55,2642Chem. 55, (1977.The effect of substituents at the 3-position in a series of N-methyl 5,6-dihydro-7H,l2H-dibenzo [c,f]azocines on the geminal coupling constants of the C-12 methylene protons has been determined. The slope of the Hammett plot of 'J us. o has been found to be + 0.20. The orientation of the methylene protons with respect to the n orbitals of the benzene ring bearing the substituent is such that no hyperconjugative effect should be present. The value of +0.20 is in contrast to a previously measured slope of -1.9 for compounds having a geometry ideal for hyperconjugative effects and substantiates the predictions of theoretical MO calculations. As a result, the reliability of this conformational dependence of p for use in conformational analysis has been strengthened.A comparison of the data for the azocines with those in the literature indicates the difference between the minimum and maximum effects of a phenyl substituent on a geminal coupling constant of an attached methylene group is 5.5 Hz. We have previously shown (l,2) that the effect of para substituents on the geminal coupling constants of the methylene protons in several series of benzylic systems was proportional to the Hammett substituent constants and that the magnitude of change in '5, represented by p, the slope of the Hammett plot, depended upon the conformation of the methylene protons with respect to the adjacent aromatic ring. This angular dependence was attributed to the fact that hyperconjugation of a benzene ring with the 'NRCC No. 15949. 'Present address: Defence Research Establishment Ottawa, Ottawa, Canada. adjacent methylene group causes a negative shift3 in J which is itself angularly dependent. Both valence bond (VB) calculations (6) and molecular orbital (MO) calculations (7) predicted a maximum effect on 'J when + = 0" and no effect when + = 90", where + is defined using the conformers shown in Fig. 1. However, in the calculations, there was a discrepancy between the predictions of the VB and MO methods in the region of + = 90". The former predicted a 3Since the geminal coupling constants in benzylic systems have been shown to be negative (3), it is most convenient to describe the effect of, for example, the phenyl group in toluene ('J = -14.8 HZ (4)) US. methane ('J = -12.4 (5)) as causing a negative shift in 'J.Can. J. Chem. Downloaded from www.nrcresearchpress.com by 54.191.190.102 on 05/11/18For personal use only.

show abstract

“…Block-diagonal least-squares minimizing Y w(AF) z where w= 1/{l+ /32] 4} and 1"0_<1Fo1_<82"3; f curves and computer programs Same as for part I (Hardy & Ahmed, 1974).…”

Section: Refinementmentioning

confidence: 99%

“…The crystal structure of N-methyldihydrodibenzazocine has been described by Hardy & Ahmed (1974) as part I of this series. X-ray structural analysis of the title compound has been undertaken in order to determine the effect on the conformation of the azocine ring system when the bulky t-butyl group replaces the methyl group on the nitrogen atom.…”

Section: Introductionmentioning

confidence: 99%

Structural studies of dibenz[c,f]azocines. II. N-t-Butyl-5,6-dihydro-7H,12H-dibenz[c,f]azocine

Hardy¹,

Ahmed²

1974

Acta Crystallogr Sect B

Self Cite

View full text Add to dashboard Cite

Crystals of the title compound, CI9H23N, are triclinic, P1, with a= 10.143, b= 9.863, c= 9-568/~, ~= 111.38, fl= 116.08, 7=91-71 °, and Z=2. The crystal structure has been determined by the symbolic addition procedure and refined by the least-squares method to R = 0.052 for the 1993 observed reflexions. The azocine ring has the twist-boat conformation with half of the molecules left-handed and the other half right-handed, but otherwise the same degree of twist for all molecules. The endocyclic angle at N is 113.0 (2) ° and the exocyclic angles are 115.1 (2) and 115.4 (2)°; mean= 114-5 °. The length of the N.• .C diagonal is 2.86 A, indicating very weak transannular interaction across the azocine ring. Some preferred localization of electronic charge is observed in the benzene rings.

show abstract

Structural studies of dibenz[c,f]azocines. I. N-Methyl-5,6-dihydro-7H,12H-dibenz[c,f]azocine

Cited by 13 publications

References 6 publications

The crystal and molecular structure of cis-1,5-bis(toluene-p-sulfonyl)-3,7-dihydroxyoctahydro-1,5-diazocine

The crystal and molecular structure of cis-1,5-bis(toluene-p-sulfonyl)-3,7-dihydroxyoctahydro-1,5-diazocine

The effect of substituents on geminal proton–proton coupling constants. III

Structural studies of dibenz[c,f]azocines. II. N-t-Butyl-5,6-dihydro-7H,12H-dibenz[c,f]azocine

Contact Info

Product

Resources

About