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• 109-72-8 n-butyllithium 
• 73434-13-6 Dibenzyl-α,α-d₂-dimethylammonium bromide 
• 583-03-9 1-Phenyl-1-pentanol 

Relevant academic research and scientific papers

Efficient and convenient heterogeneous palladium-catalyzed regioselective deuteration at the benzylic position

The Pd/C-catalyzed efficient and regioselective hydrogen-deuterium (H-D) exchange reaction on the benzylic site proceeded in D2O in the presence of a small amount of H2 gas. The use of the Pd/C-ethylenediamine complex [Pd/C(en)] as a catalyst instead of Pd/C led to the efficient deuterium incorporation into the benzylic site of Obenzyl protective groups without hydrogenolysis. These H-D exchange reactions provide a post synthetic and D2-gas-free deuterium-labeling method on a wide variety of benzylic sites using D2O as the deuterium source and heterogeneous Pd/C or Pd/C(en) as a reusable heterogeneous palladium catalyst under mild and neutral conditions.

Azetidines. 5. Reaction of 1,1,3,3-Tetramethyl- and 1-Benzyl-1,3,3-trimethylazetidinium Ions with Butyllithium and Phenyllithium. Deuterium Labeling as a Mechanistic Probe

The reactions of 1,1,3,3-tetramethylazetidinium iodide (1) and 1-benzyl-1,3,3-trimethylazetidinium bromide (7) with butyllithium and with phenyllithium were studied in ether.The products from the reaction of 1 with butyllithium were 1,3,3-trimethylpyrrolidine (2), 3,3-dimethyl-4-(methylamino)-1-butene (3), 1-(dimethylamino)-2,2-dimethylheptane (4), neopentylpyrrolidine (5), and 1-(dimethylamino)-2,2-dimethylcyclopropane (6).With phenyllithium, 1 gave 2 and 1-(dimethylamino)-2,2-dimethyl-3-phenylpropane (11).With butyllithium, 7 gave 2-phenyl-1,4,4-trimethylpyrrolidine (8), 1-benzyl-3,3-dimethylpyrrolidine (9), and 1-neopentyl-2-phenylpyrrolidine (10).The reaction of phenyllithium with 7 gave only 8 and 9.Mechanistic information was obtained by labeling 1 with deuterium in three different ways: N-methyl-d3, 2,2-d2, and N-methyl-d3-2,2-d2.A primary kinetic isotope effect of 9.4 was found for the formation of 2 from 1-N-methyl-d3.When 2 was formed from 1-2,2-d2, a secondary kinetic isotope effect of 1.17 was measured.The formation of 4 from 1-2,2-d2 was accompanied by a primary kinetic isotope effect of 4.7, suggesting a carbene intermediate.Ylide carbanions involving decomposition to a carbene carbanion in the formation of 3 and an azomethine ylide in the formation of 5 and 9 are probable intermediates.It is postulated that the azomethine ylides react with ethylene formed from the reaction of butyllithium with the solvent ether by means of a concerted (4 + 2) cycloaddition reaction.A primary kinetic isotope effect of 20 was found for the formation of pentylbenzene from dibenzyldimethylammonium bromide and butyllithium.