Mechanistic Study of the Ru-Catalyzed Asymmetric Hydrogenation of Nonchelatable and Chelatable tert-Alkyl Ketones Using the Linear Tridentate sp3P/sp3NH/sp2N-Combined Ligand PN(H)N: RuNH- and RuNK-Involved Dual Catalytic Cycle
Mechanistic Study of the Ru-Catalyzed Asymmetric Hydrogenation of Nonchelatable and Chelatable tert-Alkyl Ketones Using the Linear Tridentate sp3P/sp3NH/sp2N-Combined Ligand PN(H)N: RuNH- and RuNK-Involved Dual Catalytic Cycle
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使用线性三齿 sp3P/sp3NH/sp2N 组合配体 PN(H)N 进行 Ru 催化不可螯合和可螯合叔烷基酮不对称氢化的机理研究:RuNH 和 RuNK 参与的双催化循环
DOI:
10.1021/acscatal.8b02671
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发表时间:
2018
期刊:
影响因子:
12.9
通讯作者:
Kitamura Masato
中科院分区:
文献类型:
--
作者:
Nakane Satoshi;Yamamura Tomoya;Manna Sudipta Kumar;Tanaka Shinji;Kitamura Masato
The linear tridentate sp3P/sp3NH/sp2N ligandPN(H)N((R)-2′-(diphenylphosphino)-N-(pyridin-2-ylmethyl)[1,1′-binaphthalen]-2-amine) exclusively formsfac-[Ru(PN(H)N)(dmso)3](BF4)2over the mer isomer with the help of the three strongly π-accepting DMSO ligands. The three different ligating atoms exert a divergent effect on thetrans-DMSO—Ru bond strengths, enabling the stereoselective generation offac-RuH(CH3O)(PN(H)N)(dmso) (RuNH).RuNHefficiently hydrogenates both nonchelatablet-butyl methyl ketone (BMK) and chelatablet-butyl methoxycarbonylmethyl ketone (BMCK) in the presence of a catalytic amount of CH3OK. The reaction proceeds at the H—sp3N—Ru—H bifunctional reaction site offac-RuH2(PN(H)N)(dmso), and high enantioselectivity is attained in a chiral 3D cavity constructed by the sp3N trans DMSO, the conformation of which is fixed by a PyC(6)H—O═S hydrogen bond. We determined the structures ofRuNH, the K amideRuNK, Ru dihydride, and Ru amido species by detailed NMR analysis using15N-labeledPN(H)Nand C(3)-Ph-substitutedPN(H)N. The rate ofBMKhydrogenation is significantly affected by [CH3OK]0, showing a characteristic curve with a peak followed by a pseudo-minus-first-order decay. TheRuNHis easily deprotonated by CH3OK to generateRuNK, which is less reactive but has the same enantioface discrimination ability. Increased contribution of the slowRuNKcycle decreases the rate at higher [CH3OK]0. TheRuNH- andRuNK-involved dual catalytic cycle is supported by curve-fitting analyses and K+trapping experiments. In hydrogenation ofBMCK, only theRuNHcycle operates becauseBMCKis preferentially deprotonated overRuNH.
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DOI:
--
发表时间:
2010
期刊:
影响因子:
--
作者:
T.Seki;S.Tanaka;M.kitamura
通讯作者:
M.kitamura
影响因子:
5.2
作者:
Tanaka, S;Saburi, H;Kitamura, M
通讯作者:
Kitamura, M
影响因子:
1.8
作者:
M. Darwish;Alistair Wallace;G. Clarkson;M. Wills
通讯作者:
M. Wills
影响因子:
2.3
作者:
L. Dahlenburg;C. Kühnlein
通讯作者:
C. Kühnlein
DOI:
10.1021/om000894w
发表时间:
2001
期刊:
影响因子:
--
作者:
V. F. Kuznetsov;A. G. P. A. Yap;H. Alper
通讯作者:
H. Alper