In:
Canadian Journal of Chemistry, Canadian Science Publishing, Vol. 85, No. 7-8 ( 2007-07-01), p. 461-465
Abstract:
The 2:1 adduct of benzyne with 2-methylanisole is shown to have the bisbenzotricyclic structure 6,6a,11,11a-tetrahydro-5-methoxy-6-methyl-5,6,11-metheno-5H-benzo[a]fluorene by a single-crystal X-ray diffraction study (C 20 H 18 O: Pca2 1 , a = 15.0497(17), b = 9.87783(11), c = 9.6846(11); Z = 4; 1672 data points, R 1 = 0.0325). This structure is compared to an unpublished crystal structure of the parent hydrocarbon 6,6a,11,11a-tetrahydro-5,6,11-metheno-5H-benzo[a]fluorene, C 18 H 14 . Both structures have also been computed by DFT methods at the B3LYP/6-311(d,p) level of theory. Bond distances and angles between the solid-state measurements and gas-phase calculations are found to agree well; average deviations are well below 1%. The 1 H NMR spectra show surprisingly small 3 J HH couplings in the central tricyclic cage, but can be assigned using 2D spectroscopy.Key words: Hydrocarbon cages, strained rings, cyclopropane, X-ray crystallography, NMR.
Type of Medium:
Online Resource
ISSN:
0008-4042
,
1480-3291
Language:
English
Publisher:
Canadian Science Publishing
Publication Date:
2007
detail.hit.zdb_id:
1482256-8
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