The synthesis of the highly strained title compound 8a was achieved by the valence isomerization and in situ dehydrogenation of the cyclophanediene 7a at only 80 degrees C. A single-crystal X-ray structure determination of 8a revealed that the pyrene moiety is remarkably bent, the two ends forming an angle of 109.2 degrees. This degree of lengthwise bend slightly exceeds that present in the pyrene unit found in the equator of D-5h C-70, rendering it the most bent pyrene group yet prepared. The expectation of unusual reactivity is borne out by the apparent Diels-Alder reaction between 8a and tetracyanoethylene (TCNE) to give adduct 9.
Bodwell, Graham J.; Bridson, John N.; Houghton, Tom J., Angewandte Chemie, 1996, vol. 108, # 12, p. 1418 - 1420
作者:Bodwell, Graham J.、Bridson, John N.、Houghton, Tom J.、Kennedy, Jason W. J.、Mannion, Michael R.
DOI:——
日期:——
Nonplanar Aromatic Compounds. 3. A Proposed New Strategy for the Synthesis of Buckybowls. Synthesis, Structure and Reactions of [7]-, [8]- and [9](2,7)Pyrenophanes
作者:Graham J. Bodwell、James J. Fleming、Michael R. Mannion、David O. Miller
DOI:10.1021/jo0007027
日期:2000.8.1
A new strategy for the synthesis of Buckybowls is presented and initial attempts to implement it are reported. This involves annulation of further rings onto polycyclic aromaticsystems that prefer to be planar but have been "pre-bent" by the installation of a tether. Pyrenophane 2b reacts with TCNE and PTAD to give 1:1 and 1:2 adducts, respectively. The less strained pyrenophane 2c is unreactive toward