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.).
Amine Catalysis for the Organocatalytic Diboration of Challenging Alkenes
Farre, Albert,Soares, Kaline,Briggs, Rachel A.,Balanta, Angelica,Benoit, David M.,Bonet, Amadeu
supporting information, p. 17552 - 17556 (2016/11/28)
The generation of in situ sp2–sp3diboron adducts has revolutionised the synthesis of organoboranes. Organocatalytic diboration reactions have represented a milestone in terms of unpredictable reactivity of these adducts. However, current methodologies have limitations in terms of substrate scope, selectivity and functional group tolerance. Here a new methodology based on the use of simple amines as catalyst is reported. This methodology provides a completely selective transformation overcoming current substrate scope and functional/protecting group limitations. Mechanistic studies have been included in this report.