Hexaradialenes by successive ring openings of tris(alkoxytricyclobutabenzenes): Synthesis and characterization

Angewandte Chemie - International Edition

Volumn 49, Issue 17, 2010, Pages 3026-3029

  Shinozaki, Shinya ^a   Hamura, Toshiyuki ^a,c   Ibusuki, Yousuke ^a   Fujii, Kotaro ^a   Uekusa, Hidehiro ^a   Suzuki, Keisuke ^a,b  

^a TOKYO INSTITUTE OF TECHNOLOGY   (Japan)

^b KWANSEI GAKUIN UNIVERSITY   (Japan)

^c JAPAN SCIENCE AND TECHNOLOGY AGENCY   (Japan)

Author keywords

Diastereoselectivity; Isomerization; Radialene; Ring opening reactions; Tricyclobutabenzene

Indexed keywords

BULKY SUBSTITUENTS; DIASTEREOSELECTIVITY; FOUR-MEMBERED RINGS; HYDROXY GROUPS; ISOMERIZATION REACTION; RING OPENING REACTION; STEREO-SELECTIVE; SUCCESSIVE RINGS; SYNTHESIS AND CHARACTERIZATION; THERMALLY INDUCED; TRICYCLOBUTABENZENE;

ELECTRON TRANSITIONS; ISOMERS; STEREOSELECTIVITY; SYNTHESIS (CHEMICAL);

ISOMERIZATION;

EID: 77951164931     PISSN: 14337851     EISSN: 15213773     Source Type: Journal    
DOI: 10.1002/anie.200907305     Document Type: Article

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23. All new compounds were fully characterized by spectroscopic methods, combustion analysis, or high-resolution mass spectral analysis. For details, see the Supporting Information.
24. 2 (SHELXL97). A total of 13951 reflections were measured and 6654 were independent. Final R1 = 0.1153, wR2 = 0.2801 (4411 refs; 1>2σ(I)), and GOF = 1.095 (for all data, R1 =0.1595, wR2 = 0.3101). CCDC 759632 (12) contains the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac. uk/data-request/cif.
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37. Monoannelated product 22 consisted of two stereoisomers, which were not separable.
38. Triphenylene 21 was also produced in 5 % yield, accompanied by the starting material 10 a (37%).