Improved synthesis of Bn5CpRu(CO)(2)Cl and its application as racemization catalyst in preparative-scale metalloenzymatic dynamic kinetic resolution of 1-phenylethanol

Denys Mavrynsky, LT Kanerva, R Sillanpaa, Reko Leino

    Research output: Contribution to journalArticleScientificpeer-review

    10 Citations (Scopus)

    Abstract

    An improved gram-scale synthesis of Bn5CpRu(CO)(2)Cl is reported based on heating of pentabenzylcyclopentadiene with Ru-3(CO)(12) at 160 degrees C under argon atmosphere in mesitylene followed by addition of chloroform, continued heating, and evaporation of the solvents. Subsequent washing of unreacted ligand precursor with hexane provided pure title compound in 77 % yield. In combination with Candida antarctica lipase B (CAL-B) (Novozym 435), this complex forms a highly active racemization catalyst for metallo enzymatic dynamic kinetic resolution (DKR) of secondary alcohols as demonstrated in the present work by converting 100 g of racemic 1-phenylethanol to (R)-1-phenylethanol in > 99 % ee and 93 % overall yield over two steps using 0.05 mol % loading of the metal catalyst and 1 mass % loading of immobilized enzyme. In addition, the synthesis and crystallographic characterization of the palladium congener Bn5CpPd(PPh3)Cl are briefly discussed.
    Original languageUndefined/Unknown
    Pages (from-to)479–487
    Number of pages9
    JournalPure and Applied Chemistry
    Volume83
    Issue number3
    DOIs
    Publication statusPublished - 2011
    MoE publication typeA1 Journal article-refereed

    Keywords

    • chemoenzymatic synthesis
    • cyclopentadienyl
    • dynamic kinetic resolution (DKR)
    • Novozym
    • ruthenium

    Cite this