ISSN:
0009-2940
Keywords:
Cyclophanes
;
Indenyl anions
;
Iron complexes
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
[2.2]Metacyclophane can be directly formylated according to the Rieche method to give 4-formyl[2.2]metacyclophane (12) in 44% yield. The synthesis of the [2]metacyclo[2]indenophane 8 from the aldehyde 12 by the pathway previously employed for the corresponding [2.2]paracyclophanes failed due to the harsh conditions of the cyclization step. An alternative synthesis of 8 and its isomer 9 involving the construction of the five-membered ring prior to that of the cyclophane unit succeeded. Compounds 8 and 9 were obtained as an 82:18 mixture, deprotonation of which afforded the anion 10, which shows long-term stability. The 1H-NMR spectrum of this anion does not exhibit a through-space charge transfer due to its structure. The 1H-NMR parameters and molecular mechanics calculations are discussed. Both faces of 10 react in the presence of FeCl2 · 2 THF and a twentyfold excess of LiCp to give a 70:30 mixture of the ferrocene derivatives 7 and 35.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19931260125
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