ISSN:
0009-2940
Keywords:
7-Norcaranylidene carbenoid, substituted
;
Cycloallene dimerization
;
Tetrakis(arylmethylene)ethane diradical
;
1,2-Bismethylenecyclobutanes
;
Bisbenzo[4,5]cyclohepta[1,2-a: 2',1'-c]naphthalene, hexahydro-
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Cycloallenes, 7. - A Seven-Membered-Ring Allene Dimer: Preparation from a 7,7-Dibromonorcarane Derivative and ThermolysisPrepared by addition of dibromocarbene to 1,2-dihydro-3-phenylnaphthalene, the 7,7-dibromonorcarane derivative 6 gave the tetra- and pentacyclic hydrocarbons 7 and 8, respectively, on treatment with n-butyllithium. The formation of 8 is considered to proceed via the 1,2-cycloheptadiene derivative 15, which undergoes a dimerisation with the tetramethyleneethane diradical 16 as intermediate. Diradical 16 is also believed to be the intermediate in the thermal rearrangements of 8 to the penta- and hexacyclic hydrocarbons 12 and 13 and of 12 to 13. The structures of 8 and 13 have been determined by X-ray structure analyses. Of special interest is the unusual length (165 pm) of the C-12a - C-12b bond (C-1 - C-22 in Figure 1) in 8.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19911241128
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