J. Seetz, B. J. J. V. D. Heisteeg, G. Schat
Oct 23, 1984
Citations
0
Influential Citations
12
Citations
Journal
Journal of Organometallic Chemistry
Abstract
Abstract The reaction of 1,3-bis(bromomagnesio)-2,2-dimethylpropane (1b) with dichlorodicyclopentadienylvanadium(IV) (5) gave 1,1-dicyclopentadienyl-3,3-dimethylvanada(IV)cyclobutane (4) in 30% yield, contaminated with dicyclopentadienylneopentylvanadium(III) (12). Attempts to purify 4 were only partially successful due to its limited stability (t 1 2 = 4 h at 25°C in cyclopentane). Identification of 4 is therefore based on its having sufficient thermal stability for isolation, on its reaction with bromine to give 1,3-dibromo-2,2-dimethylpropane (2b), and especially on its ESR and 1H NMR spectra. The reaction of 4 with cyclohexanone (15) gave 17 and 18 as the main products; 17 is the aldol dimer of 15, while 18 may be derived from either 4 or 12. Because methylenecyclohexane (16) is not one of the reaction products, it is concluded that 4 does not have a pronounced tendency to fragment to give a metallacarbene (20).