Enzymes in organic synthesis. 34. Preparations of enantiomerically pure exo- and endo-bridged bicyclic [2.2.1] and [2.2.2] chiral lactones via stereospecific horse liver alcohol dehydrogenase catalyzed oxidations of meso diols

Lok, Kar P.; Jakovac, Ignac J.; Jones, J. Bryan

doi:10.1021/ja00294a052

Cited by 105 publications

(30 citation statements)

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“…[55,56] This enzyme was also applied for the asymmetrisation of prochiral meso-diols, due to its ability to discriminate between enantiotopic hydroxy groups. [57] HLADH is a reasonably stable enzyme and exhibits a certain tolerance toward many organic solvents used to solubilise lipophilic substrates; [58] the enzyme is active even in water-saturated organic solvents. [59,60] In combination with HLADH, glutamate dehydrogenase [61,62] and monooxygenases [63] have been commonly used for enzymatic NAD regeneration.…”

Section: Adhs For Preparative Applications and Their Substrate Spectrummentioning

confidence: 99%

Biocatalytic Oxidation of Primary and Secondary Alcohols

et al. 2004

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Driven by the immaturity of many organic oxidation reactions and the necessity for −green× chemical processes, biocatalytic redox processes are being investigated with increasing intensity in order to tap the full potential of the excellent chemo-, regioand enantioselectivity of enzymes. Despite their unmatched advantage in view of environmental aspects, the requirement of cofactors and the availability of redox enzymes able to tolerate high concentrations of organic (co)substrates sets limitations. However, during the past years, an increasing number of applications to the bio-oxidation of primary and secondary alcohols with novel redox enzymes have been developed. This review gives an overview on the different methods and their potential and limits.

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Section: Adhs For Preparative Applications and Their Substrate Spectrummentioning

confidence: 99%

Biocatalytic Oxidation of Primary and Secondary Alcohols

et al. 2004

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“…5 of the general part have been drawn by analogy with the series of bicyclic compounds 11a, 12a/11b, 12b, 13b/11c, 12c, 13c, without any experimental evidence! The NMR spectrum of the 6 : 4 12d/13d mixture could be interpreted, and the signals assigned by comparison with published spectra of 12d [75] and 13d [76]. 1 H-NMR (300 MHz): 12d: 1.08 ± 1.78 (m, 6 H); 2.08 ± 2.78 (m, 5 H); 4.46 ± 4.49 (m, OCH); 13d: 1.08 ± 1.78 (m, 6 H); 2.08 ± 2.78 (m, 4 H); 3.90 (dd, J 3.7, 9.6, OCH); 4.42 (d, J 9.6, OCH).…”

Section: Enantioselective Sulfoxidation Of Mesph (S)-methyl Phenyl Smentioning

confidence: 99%

Preparation of TADOOH, a Hydroperoxide from TADDOL, and Use in Highly Enantioface- and Enantiomer-Differentiating Oxidations

Aoki

Seebàch

2001

HCA

100

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Replacement of one OH group in TADDOL ( a,a,a',a'-tetraaryl-1,3-dioxolane-4,5-dimethanol) by an OOH group gives a stable, crystalline chiral hydroperoxy alcohol TADOOH ( {(4R,5R)-5-[(hydroperoxydiphenyl)methyl]-2,2-dimethyl-1,3-dioxolan-4-yl}diphenylmethanol) 3, the crystal structure of which resembles those of numerous other TADDOL derivatives (Fig. 2). The new hydroperoxide was tested as chiral oxidant in three types of reactions: the epoxidation of enones with base catalysis (Scheme 2), the sulfoxidation of methyl phenyl sulfide (Scheme 3), and the Baeyer-Villiger oxidation of bicyclic and tricyclic cyclobutanones, rac-10a ± d with kinetic resolution (Scheme 4, Fig. 3, and Table). Products of up to 99% enantiomer puritiy were isolated (the highest values yet observed for oxidations with a chiral hydroperoxide!). Mechanistic models are proposed for the stereochemical courses of the three types of reactions (Schemes 5 and 6, and Fig. 4). Results of AM1 calculations of the relative transition-state energies for the anionic rearrangements of the exo Criegee adducts of TADOOH to the enantiomeric bicyclo[3.2.0]heptan-6-ones are in qualitative agreement with the observed relative rates (Table and Fig . 5).

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“…The pH was maintained at 7.0 with 6 M NaOH. Substrate and product concentrations were determined by GC assay and the optical purity of the product was determined by chiral HPLC Recently, Lok et al (1985) have demonstrated the stereoselective oxidation of exo-and endo-bridged [2.2.1] and [2.2.2] meso diol to produce enantiomeric pure lactones. However, to oxidize I g of meso exoand endo-7-oxabicyclo[2.2.1] heptanediol, it required 720 mg of N A D +, 9.7 g FMN, and 50 mg horse liver alcohol dehydrogenase.…”

Section: Resultsmentioning

confidence: 99%

Stereoselective enzymatic hydrolysis of (exo,exo)-7-oxabicyclo[2.2.1]heptane-2,3-dimethanol diacetate ester in a biphasic system

Patel

Liu

Banerjee

et al. 1992

Appl Microbiol Biotechnol

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A key chiral intermediate lactol (3)[3aS (3aa,4a,7a,7aa)]-hexahydro-4,7-epoxy-isobenzofuran-1 (3H)-one was prepared for the total synthesis of a new thromboxane antagonist. The stereoseiective hydrolysis of (exo,exo)-7-oxabicyclo[2.2.1]heptane-2,3-dimethanol, diacetate ester (1) to the corresponding chiral monoacetate ester (2) was carried out with lipases, among which Amano P-30 lipase from Pseudomonas sp. was most effective since it gave the desired enantiomer of monoacetate ester. A yield of 75 mol% and optical purity of > 99% was obtained when the reaction was conducted in a biphasic system with 10% toluene at 5 g/l of the substrate. Lipase P-30 was immobilized on Accurel polypropylene (PP) and the immobilized enzyme was reused (five cycles) without loss of enzyme activity, productivity or optical purity. The reaction process was scaled-up to 80 1 (400 g substrate) and monoacetate (2) was isolated in 80 mol % yield with 99.3% optical purity as determined by chiral HPLC and nuclear magnetic resonance (NMR) analysis. A gas chromatography of 99.5% and specific rotation, [a]D of --7.6 ° was obtained. The chiral monoacetate ester (2) was oxidizedto its corresponding aldehyde and subsequently hydrolyzed to give lactol (3).

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Enzymes in organic synthesis. 34. Preparations of enantiomerically pure exo- and endo-bridged bicyclic [2.2.1] and [2.2.2] chiral lactones via stereospecific horse liver alcohol dehydrogenase catalyzed oxidations of meso diols

Cited by 105 publications

References 0 publications

Biocatalytic Oxidation of Primary and Secondary Alcohols

Biocatalytic Oxidation of Primary and Secondary Alcohols

Preparation of TADOOH, a Hydroperoxide from TADDOL, and Use in Highly Enantioface- and Enantiomer-Differentiating Oxidations

Stereoselective enzymatic hydrolysis of (exo,exo)-7-oxabicyclo[2.2.1]heptane-2,3-dimethanol diacetate ester in a biphasic system

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