22520-19-0Relevant articles and documents
Structural Study of Bromide-Bridged Pd Chain Complex with Weak CH···O Hydrogen Bonds
Rasel Mian, Mohammad,Iguchi, Hiroaki,Miyata, Momoka,Takaishi, Shinya,Yamakawa, Hiromichi,Terashige, Tsubasa,Miyamoto, Tatsuya,Okamoto, Hiroshi,Yamashita, Masahiro
, p. 646 - 651 (2018/08/06)
A novel Br-bridged Pd chain complex, [Pd(hxn)2Br](TsO)2 (2) (TsO– = p-toluenesulfonate), was synthesized from a new in-plane ligand (3S,4S)-3,4-diaminohexane (hxn). 2 forms PdII/PdIV mixed-valence state, as confirmed by single-crystal X-ray structure analysis and polarized Raman spectra. The hxn ligand provides the additional hydrogen bonds (CH···O) between the methyl group of the ligands and the O atoms of TsO– anions, which are weaker than those observed in the chain complex with hydroxy group, [Pd(dabdOH)2Br]Br2 (1).
Hydrogen Bonding-Assisted Enhancement of the Reaction Rate and Selectivity in the Kinetic Resolution of d,l-1,2-Diols with Chiral Nucleophilic Catalysts
Fujii, Kazuki,Mitsudo, Koichi,Mandai, Hiroki,Suga, Seiji
supporting information, p. 2778 - 2788 (2017/08/23)
An extremely efficient acylative kinetic resolution of d,l-1,2-diols in the presence of only 0.5 mol% of binaphthyl-based chiral N,N-4-dimethylaminopyridine was developed (selectivity factor of up to 180). Several key experiments revealed that hydrogen bonding between the tert-alcohol unit(s) of the catalyst and the 1,2-diol unit of the substrate is critical for accelerating the rate of monoacylation and achieving high enantioselectivity. This catalytic system can be applied to a wide range of substrates involving racemic acyclic and cyclic 1,2-diols with high selectivity factors. The kinetic resolution of d,l-hydrobenzoin and trans-1,2-cyclohexanediol on a multigram scale (10 g) also proceeded with high selectivity and under moderate reaction conditions: (i) very low catalyst loading (0.1 mol%); (ii) an easily achievable low reaction temperature (0 °C); (iii) high substrate concentration (1.0 M); and (iv) short reaction time (30 min). (Figure presented.).
Selective transition-metal-free vicinal cis-dihydroxylation of saturated hydrocarbons
Bering, Luis,Antonchick, Andrey P.
, p. 452 - 457 (2016/12/30)
A transition-metal-free cis-dihydroxylation of saturated hydrocarbons under ambient reaction conditions has been developed. The described approach allows a direct and selective synthesis of vicinal diols. The new reaction thereby proceeds via radical iodination and a sequence of oxidation steps. A broad scope of one-pot dual C(sp3)-H bond functionalization for the selective synthesis of vicinal syn-diols was demonstrated.