메뉴 건너뛰기




Volumn 38, Issue 1-2, 1999, Pages 179-181

New diphosphate ligands for catalytic asymmetric hydrogenation: The crucial role of conformationally enantiomeric diols

Author keywords

Asymmetric hydrogenations; Chirality; Homogeneous catalysis; P ligands; Rhodium

Indexed keywords

LIGAND; RHODIUM;

EID: 0033555638     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/(sici)1521-3773(19990115)38:1/2<179::aid-anie179>3.0.co;2-z     Document Type: Article
Times cited : (189)

References (24)
  • 6
    • 0344280194 scopus 로고
    • Brunner and Wink used chiral diphosphite ligands based on carbohydrates and tartaric acid derivatives in Rh-catalyzed hydrogenations and obtained ee values of 1-34 %: a) H. Brunner, W. Pieronczyk, J. Chem. Res. Synop. 1980, 76;
    • (1980) J. Chem. Res. Synop. , vol.76
    • Brunner, H.1    Pieronczyk, W.2
  • 19
    • 0000010553 scopus 로고
    • b) Bakos et al. synthesized the corresponding 2,5-bis(diphenylphosphino)idite from ditosylated 1,4:3,6-dianhydro-D-mannite by means of double nucleophilic substitution under inversion of configuration with lithium diphenylphosphide and used this nonchelating diphosphane in the asymmetric Rh-catalized hydrogenation (ee = 21-58%): J. Bakos, B. Heil, L. Marko, J. Organomet. Chem. 1983. 253, 249-252.
    • (1983) J. Organomet. Chem. , vol.253 , pp. 249-252
    • Bakos, J.1    Heil, B.2    Marko, L.3
  • 20
    • 0344280193 scopus 로고    scopus 로고
    • note
    • These results were obtained with preformed catalysts. If the hydrogenation is carried out with catalysts formed in situ. no differences in selectivity are observed. Both ligands lead to similarly high conversions and selectivities, the results for the S-selective ligand 4b being subject to variation: 4b (conversion 73-98%; ee = 89-95% (S)); 4c (conversion >99%: ee = 93.5% (R)). In contrast, the hydrogenation with 4e leads to identical results with catalyst formed in situ and with preformed catalyst.
  • 22
    • 0345574153 scopus 로고    scopus 로고
    • note
    • Detailed kinetic studies are under way in cooperation with T. Rosner and D. Blackmond (Max-Planck-Institut für Kohlenforschung).
  • 23
    • 85088333083 scopus 로고    scopus 로고
    • note
    • 31P NMR signal.
  • 24
    • 0344280192 scopus 로고    scopus 로고
    • note
    • The force-field calculations were carried out with the SYBYL program (Tripos Ass. Inc.). Other than the lowest energy pair of enantiomers 7a/7b. no minimum was found for an achiral conformer. We thank Dr. K. Angermund for performing the calculations.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.