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Whereas lithium 2,2,6,6-tetramethylpiperidide (LITMP) abstrs. a proton exclusively from the 4-position of 3-bromobenzotrifluoride, the same base attacks selectively the 2-position when employed in the presence of N,N,N',N'',N''-pentamethyldiethylenetriamin ...
The present thesis work provides new insight into the generation of allylmetal species and into their reactivity toward electrophiles. endo-Allylpotassiums are known to be more stable than their corresponding exo-isomers. The ring strain of methylenecycloa ...
When 3-fluoro- and 3-chloro-1,2-didehydrobenzenes are generated in the presence of 2-(trimethylsilyl)furan, two regioisomeric cycloadducts are formed in a 1:2 ratio. However, regioselectivity can be installed by fitting one bulky trimethylsilyl group into ...
The order of reactivity (X = F < Cl < Br < I) determined for the reaction of the model nucleophile pinenylpotassium with halotrimethylsilanes XSi(CH3)(3) in hexane and with halotriisopropylsilanes XSi(iC(3)H(7))(3) in tetrahydrofuran supports a single-step ...
The metalation of 2,3-, 2,6-, 2,4- and 3,5-dichlorobenzotrifluorides can be readily effected with std. reagents such as lithium diisopropylamide, lithium 2,2,6,6-tetramethylpiperidide, and butyllithium at the chlorine-adjacent 4- and 3-positions and the ch ...
A trimethyl-, triethyl-, or triisopropylsilyl group attached to the meta position of toluene retards the rate of permutational H/metal interconversion with butyllithium in the presence of K tert-butoxide by factors of 1.7, 3, and 7, resp. Although remote f ...
