TY - JOUR
T1 - Mechanistic insights into the reactions of hydride transfer versus hydrogen atom transfer by a trans-dioxoruthenium(vi) complex
AU - Dhuri, Sunder N.
AU - Lee, Yong Min
AU - Seo, Mi Sook
AU - Cho, Jaeheung
AU - Narulkar, Dattaprasad D.
AU - Fukuzumi, Shunichi
AU - Nam, Wonwoo
N1 - Publisher Copyright:
© The Royal Society of Chemistry 2015.
PY - 2015/4/28
Y1 - 2015/4/28
N2 - A mononuclear high-valent trans-dioxoruthenium(vi) complex, trans-[RuVI(TMC)(O)2]2+ (TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), was synthesized and characterized by various spectroscopic techniques and X-ray crystallography. The reactivity of the trans-[RuVI(TMC)(O)2]2+ complex was investigated in hydride transfer and hydrogen atom transfer reactions. The mechanism of hydride transfer from dihydronicotinamide adenine dinucleotide (NADH) analogues to trans-[RuVI(TMC)(O)2]2+, which proceeds via a proton-coupled electron transfer (PCET), followed by a rapid electron transfer (ET), has been proposed by the observation of a good linear correlation between the log rate constants of trans-[RuVI(TMC)(O)2]2+ and p-chloranil (Cl4Q) and a large kinetic isotope effect (KIE) value of 13(1). In the case of the oxidation of alkyl hydrocarbons by the trans-[RuVI(TMC)(O)2]2+ complex, the second-order rate constants were dependent on the C-H bond dissociation energy (BDE) of the substrates, and a large KIE value of 26(2) was obtained in the oxidation of xanthene and deuterated xanthene-d2 by the trans-[RuVI(TMC)(O)2]2+ complex, indicating that the C-H bond activation of alkyl hydrocarbons proceeds via an H-atom abstraction in the rate-determining step.
AB - A mononuclear high-valent trans-dioxoruthenium(vi) complex, trans-[RuVI(TMC)(O)2]2+ (TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), was synthesized and characterized by various spectroscopic techniques and X-ray crystallography. The reactivity of the trans-[RuVI(TMC)(O)2]2+ complex was investigated in hydride transfer and hydrogen atom transfer reactions. The mechanism of hydride transfer from dihydronicotinamide adenine dinucleotide (NADH) analogues to trans-[RuVI(TMC)(O)2]2+, which proceeds via a proton-coupled electron transfer (PCET), followed by a rapid electron transfer (ET), has been proposed by the observation of a good linear correlation between the log rate constants of trans-[RuVI(TMC)(O)2]2+ and p-chloranil (Cl4Q) and a large kinetic isotope effect (KIE) value of 13(1). In the case of the oxidation of alkyl hydrocarbons by the trans-[RuVI(TMC)(O)2]2+ complex, the second-order rate constants were dependent on the C-H bond dissociation energy (BDE) of the substrates, and a large KIE value of 26(2) was obtained in the oxidation of xanthene and deuterated xanthene-d2 by the trans-[RuVI(TMC)(O)2]2+ complex, indicating that the C-H bond activation of alkyl hydrocarbons proceeds via an H-atom abstraction in the rate-determining step.
UR - http://www.scopus.com/inward/record.url?scp=84927925669&partnerID=8YFLogxK
U2 - 10.1039/c5dt00809c
DO - 10.1039/c5dt00809c
M3 - Article
C2 - 25811701
AN - SCOPUS:84927925669
SN - 1477-9226
VL - 44
SP - 7634
EP - 7642
JO - Dalton Transactions
JF - Dalton Transactions
IS - 16
ER -