1346508-93-7Relevant articles and documents
Scope, Limitations and Mechanistic Analysis of the HyperBTM-Catalyzed Acylative Kinetic Resolution of Tertiary Heterocyclic Alcohols**
Smith, Samuel M.,Greenhalgh, Mark D.,Feoktistova, Taisiia,Walden, Daniel M.,Taylor, James E.,Cordes, David B.,Slawin, Alexandra M. Z.,Cheong, Paul Ha-Yeon,Smith, Andrew D.
supporting information, (2021/11/16)
The full scope and limitations of the catalytic acylative kinetic resolution of a range of tertiary heterocyclic alcohols (78 examples, s up to >200) is reported under operationally-simple conditions, using low loadings of a commercially available Lewis basic isothiourea catalyst, HyperBTM (generally 1 mol %). The protocol is highly effective for the kinetic resolution of 3-substituted 3-hydroxyoxindole and α-substituted α-hydroxylactam derivatives bearing up to three potential recognition motifs at the stereogenic tertiary carbinol center. The full power of this methodology has been showcased through the synthesis of highly enantioenriched biologically-active target compounds in both enantiomeric forms. To provide further insight into the reaction mechanism, a detailed kinetic analysis of this Lewis base-catalyzed acylation of tertiary alcohols is reported using the variable time normalization analysis (VTNA) method.
Evaluating polymer-supported isothiourea catalysis in industrially-preferable solvents for the acylative kinetic resolution of secondary and tertiary heterocyclic alcohols in batch and flow
Guha, Nitul Ranjan,Neyyappadath, Rifahath M.,Greenhalgh, Mark D.,Chisholm, Ross,Smith, Samuel M.,McEvoy, Megan L.,Young, Claire M.,Rodríguez-Escrich, Carles,Pericàs, Miquel A.,H?hner, Georg,Smith, Andrew D.
supporting information, p. 4537 - 4546 (2018/10/17)
Polymer-supported Lewis base catalysts, based on the homogeneous isothioureas HyperBTM and BTM, have been synthesised and applied for the acylative kinetic resolution of secondary and tertiary heterocyclic alcohols. In batch, the use of industrially-preferable solvents was investigated, with dimethyl carbonate proving to be most generally-applicable. Significantly, the HyperBTM-derived immobilised catalysts were readily recycled, with no loss in either activity or selectivity. In addition to the kinetic resolution of secondary benzylic, propargylic, allylic and cycloalkanol derivatives, a range of 22 tertiary heterocyclic alcohols, based on privileged 3-hydroxyoxindole and 3-hydroxypyrrolidinone substructures, were resolved with up to excellent selectivity (s = 7-190). Finally, the immobilised isothiourea catalysts were applied in a packed bed reactor to demonstrate the first example of the kinetic resolution of tertiary heterocyclic alcohols in a continuous flow process. High selectivities were obtained for the resolution of 3-hydroxyoxindole derivatives in ethyl acetate (s up to 70); and for 3-hydroxypyrrolidinones derivatives in toluene (s up to 42).
Axial tri-tert-butylphosphane coordination to Rh2(OAc)4: Synthesis, structure, and catalytic studies
Tan, Jiantao,Kuang, Yi,Wang, Yi,Huang, Qingfei,Zhu, Jin,Wang, Yuanhua
supporting information, p. 3139 - 3147 (2016/10/09)
The introduction of strong σ-donor axial ligands to the Rh-Rh metal bond has been utilized as an effective way to provide new chemical reactivities to bimetallic dirhodium(II) complexes. In this report, Rh2(OAc)4 complexes with axial
