Conformational analysis of molecular machines: Internal rotation and enantiomerization in triptycyl[3]helicene

ChemPhysChem

Volumn 9, Issue 8, 2008, Pages 1117-1119

  Llunell, Miquel ^a   Alemany, Pere ^a   Bofill, Josep Maria ^a  

^a UNIVERSITY OF BARCELONA   (Spain)

Author keywords

Chirality; Conformation analysis; DFT calculations; Molecular devices; Stereodynamic behavior

Indexed keywords

CHIRALITY;

CONFORMATION ANALYSIS; CONFORMATIONAL ANALYSIS; DFT CALCULATION; ENANTIOMERIZATION; INTERNAL ROTATIONS; MOLECULAR DEVICE; MOLECULAR MACHINES; STEREODYNAMIC BEHAVIOR;

DEGREES OF FREEDOM (MECHANICS);

EID: 45549102751     PISSN: 14394235     EISSN: 14397641     Source Type: Journal    
DOI: 10.1002/cphc.200800052     Document Type: Article

References (17)

1. a) E. R. Kay, D. A. Leigh, F. Zerbetto, Angew. Chem. 2007, 119, 72-196;
2. Angew. Chem. Int. Ed. 2007, 46, 72-191;
3. b) V. Balzani, M. Venturi, A. Credi, Molecular Devices and Machines. A Journey into the Nanoworld, Wiley-VCH, Weinheim, 2003.
4. a) T. R. Kelly, I. Tellitu, J. P. Sestelo, Angew. Chem. 1997, 109, 1969-1972;
5. Angew. Chem. Int. Ed. Engl. 1997, 36, 1866-1868;
6. b) T. R. Kelly, J. P. Sestelo, I. Tellitu, J. Org. Chem. 1998, 63, 3655-3665.
7. A. P. Davis, Angew. Chem. 1998, 110, 953-954;
8. Angew. Chem. Int. Ed. 1998, 37, 909-910.
9. a) R. H. Janke, G. Haufe, E.-U. Würthwein, J. H. Borkent, J. Am. Chem. Soc. 1996, 118, 6031-6035;
10. b) S. Grimme, S. D. Peyerimhoff, Chem. Phys. 1996, 204, 411-417.
11. L. Salem, Acc. Chem. Res. 1971, 4, 322-328.
12. K. Mislow, Introduction to Stereochemistry, Benjamin, New York, 1966.
13. D. M. Walba, Tetrahedron 1985, 41, 3161-3212.
14. H and the procedure followed to construct the 2D PES shown in Figure 4 can be found in the Supporting Information accompanying this work.
15. For aromatic compounds like [n]helicenes, it has been found that the singlet state obtained using an unrestricted broken symmetry method is more stable that the closed-shell singlet state, see for example, M. Bendikov et al., J. Am. Chem. Soc. 2004, 126, 7416-7417; erratum, M. Bendikov et al., J. Am. Chem. Soc. 2004, 126, 10493. Thus, unrestricted calculations at the AM1 level (M. J. S. Dewar et al., J. Am. Chem. Soc. 1985, 107, 3902-3909) have been performed using Gaussian. (Gaussian03, Revision B.4, M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R. Cheeseman, J. A. Montgomery, Jr., T. Vreven, K. N. Kudin, J. C. Burant, J. M. Millam, S. S. Iyengar, J. Tomasi, V. Barone, B. Mennucci, M. Cossi, G. Scalmani, N. Rega, G. A. Petersson, H. Nakatsuji, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, M. Klene, X. Li, J. E. Knox, H. P. Hratchian, J. B. Cross, C. Adamo, J. Jaramillo, R. Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J. W. Ochterski, P. Y. Ayala, K. Morokuma, G. A. Voth, P. Salvador, J. J. Dannenberg, V. G. Zakrzewski, S. Dapprich, A. D. Daniels, M. C. Strain, O. Farkas, D. K. Malick, A. D. Rabuck, K. Raghavachari, J. B. Foresman, J. V. Ortiz, Q. Cui, A. G. Baboul, S. Clifford, J. Cioslowski, B. B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. L. Martin, D. J. Fox, T. Keith, M. A. Al-Laham, C. Y. Peng, A. Nanayakkara, M. Challacombe, P. M. W. Gill, B. Johnson, W. Chen, M. W. Wong, C. Gonzalez, J. A. Pople, Gaussian, Inc., Wallingford CT, 2003.).
16. a) K. Mislow, Science 1954, 120, 232-233;
17. b) K. Mislow, R. Bolstad, J. Am. Chem. Soc. 1955, 77, 6712-6713.