Mechanism of hydrogen transfer to imines from a hydroxycyclopentadienyl ruthenium hydride. Support for a stepwise mechanism.
نویسندگان
چکیده
The negligible double kinetic deuterium isotope effect (k(HH)/k(DD)= 1.05) in the reaction where [2,3,4,5-Ph4(eta5-C4COH)Ru(CO)2H (2) transfers a hydride and a proton to N-phenyl-[1-(4-methoxyphenyl)ethylidene]amine (4) indicates that no bond to hydrogen is broken or formed in the rate-determining step.
منابع مشابه
Reduction of imines by hydroxycyclopentadienyl ruthenium hydride: intramolecular trapping evidence for hydride and proton transfer outside the coordination sphere of the metal.
Reduction of imines by [2,5-Ph2-3,4-Tol2(eta(5)-C4COH)]Ru(CO)2H (2) produces kinetically stable ruthenium amine complexes. Reduction of an imine by 2 in the presence of an external amine trap gives only the complex of the newly generated amine. Reaction of 2 with H2N-p-C6H4N=CHPh (11), which contains an intramolecular amine trap, gave a 1:1 mixture of [2,5-Ph2-3,4-Tol2(eta(4)-C4CO)](CO)2RuNH(CH...
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At high temperatures in toluene, [2,5-Ph(2)-3,4-Tol(2)(eta(5)-C(4)COH)]Ru(CO)(2)H (3) undergoes hydrogen elimination in the presence of PPh(3) to produce the ruthenium phosphine complex [2,5-Ph(2)-3,4-Tol(2)-(eta(4)-C(4)CO)]Ru(PPh(3))(CO)(2) (6). In the absence of alcohols, the lack of RuH/OD exchange, a rate law first order in Ru and zero order in phosphine, and kinetic deuterium isotope effec...
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ورودعنوان ژورنال:
- Chemical communications
دوره 23 شماره
صفحات -
تاریخ انتشار 2004