Chemistry is the science of change. But why do chemical reactions take place? Why do chemicals react with each other? The answer is in thermodynamics and kinetics, Recommanded Product: O-Methylisourea hemisulfate, 52328-05-9, Name is O-Methylisourea hemisulfate, SMILES is N=C(N)OC.N=C(N)OC.O=S(O)(O)=O, belongs to amides-buliding-blocks compound. In a document, author is Hu, Qiyan, introduce the new discover.
The linear tridentate sp(3)P/sp(3)NH/sp(2)N ligand PN(H)N ((R)-2′-(diphenylphosphino)-N-(pyridin-2-ylmethyl)[1,1′- binaphthalen]-2-amine) exclusively forms fac[Ru(PN(H)N)(dmso)(3)](BF4)(2) over the mer isomer with the help of the three strongly pi-accepting DMSO ligands. The three different ligating atoms exert a divergent effect on the trans-DMSO Ru bond strengths, enabling the stereo selective generation of fac-RuH(CH3O)(PN(H)N)(dmso) (RuNH). RuNH efficiently hydrogenates both nonchelatable t-butyl methyl ketone (BMK) and chelatable t-butyl methoxycarbonylmethyl ketone (BMCK) in the presence of a catalytic amount of CH3OK. The reaction proceeds at the H-sp(3)N-Ru-H bifunctional reaction site of fac-RuH2(PN(H)N)(dmso), and high enantioselectivity is attained in a chiral 3D cavity constructed by the sp(3)N trans DMSO, the conformation of which is fixed by a PyC(6)H-O=S hydrogen bond. We determined the structures of RuNH, the K amide RuNK, Ru dihydride, and Ru amido species by detailed NMR analysis using N-15-labeled PN(H)N and C(3)-Ph-substituted PN(H)N. The rate of BMK hydrogenation is significantly affected by [CH3OK](0), showing a characteristic curve with a peak followed by a pseudo-minus-first-order decay. The RuNH is easily deprotonated by CH3OK to generate RuNK, which is less reactive but has the same enantioface discrimination ability. Increased contribution of the slow RuNK cycle decreases the rate at higher [CH3OK](0). The RuNH- and RuNK-involved dual catalytic cycle is supported by curve-fitting analyses and K+ trapping experiments. In hydrogenation of BMCK, only the RuNH cycle operates because BMCK is preferentially deprotonated over RuNH.
A reaction mechanism is the microscopic path by which reactants are transformed into products. Each step is an elementary reaction. In my other articles, you can also check out more blogs about 52328-05-9. Recommanded Product: O-Methylisourea hemisulfate.
Reference:
Amide – Wikipedia,
,Amide – an overview | ScienceDirect Topics