(α,β-Substituted bis(cyclopentadienyl)titanacyclobutanes and their role in productive metathesis
作者:Daniel A. Straus、Robert H. Grubbs
DOI:10.1016/0304-5102(85)87013-9
日期:1985.1
produces a variety of C1 to C5 hydrocarbons upon thermaldecomposition. Evidence for competitive cleavage of the cis-α,β-dimethylmetallacycle to give a titanocene ethylidene or a titanocene methylene is presented. The cis-α,β-dimethyl-metallacycle (as well as Cp2 and has been found to catalyze the metathesis of cis,cis- and trans,trans-2,8-decadiene in low yield with moderate stereospecificity. The mechanism
Esr studies of the ring opening of cyclopropane radical cations in freon matrices
作者:Xue-Zhi Qin、Francon Williams
DOI:10.1016/s0040-4020(01)88093-5
日期:1986.1
matrix, however, the ring-closed radicalcations initially formed at 77 K undergo ringopening between 83 and 110 K, the more highly substituted radicalcations requiring a higher temperature for this transformation. The ring-closed radicalcations are 2A1 species for C2v symmetry, the most substituted cyclopropane C-C bond being elongated with the spin density largely confined to the basal carbons
dimethylcyclopropanes to give ring cleavage additioncompounds. IR and NMR data support structures with dichloroboryl groups in the 1,3 position of the hydrocarbon chain. Some evidence is presented to support a stereospecific reaction which involves a 4-centered transition state comparable to that which has been postulated for subchloride addition to olefins. No reaction occurs with 1,1-dichlorocyclopropane