Synthesis of Longitudinally Twisted Polycyclic Aromatic Hydrocarbons via a Highly Substituted Aryne

Journal of Organic Chemistry

Volumn 55, Issue 6, 1990, Pages 1937-1940

  Smyth, Natalie ^a   Van Engen, Donna ^a   Pascal, Robert A ^a  

^a PRINCETON UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001563307     PISSN: 00223263     EISSN: 15206904     Source Type: Journal    
DOI: 10.1021/jo00293a046     Document Type: Article

References (12)

1. Pascal, R. A., Jr.; McMillan, W. D.; Van Engen, D. J. Am. Chem. Soc. 1986, 108, 5652–5653.
2. Pascal, R. A., Jr.; McMillan, W. D.; Van Engen, D.; Eason, R. G. J. Am. Chem. Soc. 1987, 109, 4660–4665.
3. Allinger, N. L. QCPE MM2(85), 1986.
4. Dilthey, W.; ter Horst, I.; Schommer, W. J. Prakt. Chem. 1935, 143, 189–210.
5. Ogliaruso, M. A.; Romanelli, M. G.; Becker, E. I. Chem. Rev. 1965, 65, 261–367.
6. The twists in compounds 2, 8, and 9 were defined as illustrated in the following examples, which refer to the crystallographic numbering schemes for compounds 8 and 9 shown in Figure 1. To calculate the twist for the anthracene moiety of 8, the centroids of carbons 8 and 9 [X(1)J and 19 and 20 [X(2)] were located, and dummy atoms were assigned to these positions. The twist is the dihedral angle of the type C(8)-X(1)-X(2)-C(20). The twist angles for linear acene groups in 2 and 9 were calculated similarly. To obtain the overall twist of compound 9 dummy atoms were assigned to the centroids of carbons 8 and 9 [X{3)], and 24 and 26 [X(4)]. The end-to-end twist of 9 is the dihedral angle C(8)-X-(3)-X(4)-C(26).
7. The estimated standard deviations for the nuclear twist angles were calculated by the method of Stanford and Waser: Stanford, R. H.; Waser, J. Acta Crystallogr. A 1972, 28, 213–215.
8. Clar, E.; Stephen, J. F. Tetrahedron 1964, 20, 1559–1566.
9. Clar, E.; McCallum, A. Tetrahedron 1960, 10, 171–174.
10. Fagan, P. J.; Ward, M. D.; Caspar, J. V.; Calabrese, J. C.; Krusic, P. J. J. Am. Chem. Soc. 1988, 110, 2981–2983.
11. With the program MM2(85), it is not possible to distinguish true energy minima from very shallow gradients.
12. We have observed a similar C, conformation in the crystal structure of the related polycycle 9,11,20, 22-tetraphenyltetrabenzo[o,c,-l,n]pentacene-10,21-dione: Pascal, R. A., Jr.; Van Engen, D. Tetrahedron Lett. 1987, 28, 293–294.