Lipase-catalyzed kinetic resolution of Z-configured homoallylic alcohols

Adam, Waldemar; Saha‐Möller, Chantu R.; Schmid, Katharina S.

doi:10.1016/s0957-4166(98)00511-4

Cited by 12 publications

(9 citation statements)

References 11 publications

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“…Thus, desilylation of (+)-1 with toluenesulfonic acid in acetonitrile/ water (6:1) gave the known homoallylic alcohol (S)-12 (Scheme 5, 60% yield). 19 The configuration in this enantioselection is in accordance with the established empirical rule proposed by Kazlauskas et al 26 for the lipasecatalyzed kinetic resolution of secondary alcohols. To obtain the (R)-1 alcohol, the acetate (R)-11 was hydrolyzed quantitatively by K 2 CO 3 in methanol (90% ee, Scheme 5).…”

Section: Resultssupporting

confidence: 85%

“…The S configuration of the hydroxy vinylsilane (+)- 1 was determined by chemical correlation. Thus, desilylation of ( + )- 1 with toluenesulfonic acid in acetonitrile/water (6:1) gave the known homoallylic alcohol ( S )- 12 (Scheme , 60% yield) . The configuration in this enantioselection is in accordance with the established empirical rule proposed by Kazlauskas et al for the lipase-catalyzed kinetic resolution of secondary alcohols.…”

Section: Resultssupporting

confidence: 80%

“…17 For the Fleming oxidation (oxidative desilylation) 18 of the dimethylphenylsilyl to the hydroxy group by treatment with Br 2 -AcOOH under retention of the configuration, the alcohol functionalities in the tetrahydrofurans 7 were protected by acetylation. Under standard conditions, 19 the diacetates 9 were synthesized in 80-90% yield (Scheme 4). The oxidation by KBr-AcOOH gave both anomers of the 4,6-dideoxyfuranoses 10a (R:β ) 55: 45, 57% yield) and 10b (R:β ) 70:30, 62% yield).…”

Section: Resultsmentioning

confidence: 99%

“…As reference samples for the chiral HPLC analysis, it was necessary to prepare the racemic acetate 11 by acetylation of the alcohol 1 with acetic anhydride under basic conditions (92% yield). 19 a Conversion and mass balance (mb) were determined by NMR spectroscopy after silica gel chromatography. b Product ratios after silica gel chromatography, determined by NMR spectroscopy (error (5% of the stated values), except entries 5 and 11, which were analyzed as crude reaction mixtures.…”

Section: Resultsmentioning

confidence: 99%

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Synthesis of 4,6-Dideoxyfuranoses through the Regioselective and Diastereoselective Oxyfunctionalization of a Dimethylphenylsilyl-Substituted Chiral Homoallylic Alcohol

2001

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The 4,6-dideoxyfuranoses 10a and 10b have been synthesized by starting from the readily available E-5-dimethylphenylsilyl-2-hexene-4-ol (1) and employing successively three versatile oxyfunctionalization methods, namely photooxygenation, metal-catalyzed epoxidation, and oxidative desilylation. Photooxygenation of the hydroxy vinylsilane 1 and subsequent triphenylphosphine reduction of the hydroperoxides 3 afford the like-4a and unlike-4b diols, which have been converted separately to the tetrahydrofurans (2S*,3R*,5R*)-7a and (2S*,3R*,5S*)-7b by a combination of diastereoselective epoxidation and regioselective intramolecular epoxide-ring opening. In the epoxidation reaction, catalyzed by Ti(OiPr)(4) or VO(acac)(2), only one diastereomer (dr >95:5) of the epoxide 5 is obtained. Further intramolecular opening of the epoxide ring in erythro-5 occurs regioselectively at the C-alpha position and diastereoselectively under inversion of the configuration of the silyl-substituted stereogenic center to generate only one diastereomer of the tetrasubstituted tetrahydrofurans 7. Oxidative desilylation of the latter gave the hitherto unknown 4,6-dideoxyfuranoses 10a and 10b. The use of the optically active E-5-dimethylphenylsilyl-2-hexene-4-ol (1) as starting material, which is readily available through lipase-catalyzed kinetic resolution, leads to the D- and L-4,6-dideoxysorbofuranoses 10a and D- and L-4,6-dideoxyfructofuranoses 10b in up to 98% enantiomeric excess.

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Section: Resultssupporting

confidence: 85%

Section: Resultssupporting

confidence: 80%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Synthesis of 4,6-Dideoxyfuranoses through the Regioselective and Diastereoselective Oxyfunctionalization of a Dimethylphenylsilyl-Substituted Chiral Homoallylic Alcohol

2001

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“…Transacylation of alcohol 1 d has been reported by use of Burkholderia sp. lipase (four days, 52 % conversion, E = 28) [26] and by an immobilized preparation from Manihot esculenta roots (five days, 20 % conversion, E = 4). [27] Alcohol 1 f has been previously subjected to Burkholderia cepacia lipase-catalyzed hydrolysis [28] and transacylation, [29] and alcohol 1 g to hydrolysis by the same enzyme.…”

Section: Resultsmentioning

confidence: 99%

Mutant Lipase‐Catalyzed Kinetic Resolution of Bulky Phenyl Alkyl sec‐Alcohols: A Thermodynamic Analysis of Enantioselectivity

2010

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The size of the stereoselectivity pocket of Candida antarctica lipase B limits the range of alcohols that can be resolved with this enzyme. These steric constrains have been changed by increasing the size of the pocket by the mutation W104A. The mutated enzyme has good activity and enantioselectivity toward bulky secondary alcohols, such as 1-phenylalkanols, with alkyl chains up to eight carbon atoms. The S enantiomer was preferred in contrast to the wild-type enzyme, which has R selectivity. The magnitude of the enantioselectivity changes in an interesting way with the chain length of the alkyl moiety. It is governed by interplay between entropic and enthalpic contributions and substrates with long alkyl chains are resolved best with E values higher than 100. The enantioselectivity increases with temperature for the small substrates, but decreases for the long ones.

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ChemInform Abstract: Lipase‐Catalyzed Kinetic Resolution of Z‐Configured Homoallylic Alcohols.

1999

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biochemical syntheses, microbiological syntheses biochemical syntheses, microbiological syntheses O 0035 -042Lipase-Catalyzed Kinetic Resolution of Z-Configured Homoallylic Alcohols.-Successful resolution is achieved in the case of alcohols (IIIa) and (IIIb), whereas the analogues with R: -iPr or -tBu do not react. Excellent results for alcohol and acetate product concerning the e.e. value are obtained with (IIIa); the phenyl derivative (IIIb) affords either good e.e. for the alcohol or the acetate. The saturated analogue (VI) is resolved with good e.e. for both products. -(ADAM, WALDEMAR; SAHA-MOELLER, CHANTU R.; SCHMID, KATHARINA S.; Tetrahedron: Asymmetry 10 (1999) 2, 315-322; Inst. Org. Chem., Julius-Maximilians-Univ.,

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Lipase-catalyzed kinetic resolution of Z-configured homoallylic alcohols

Cited by 12 publications

References 11 publications

Synthesis of 4,6-Dideoxyfuranoses through the Regioselective and Diastereoselective Oxyfunctionalization of a Dimethylphenylsilyl-Substituted Chiral Homoallylic Alcohol

Synthesis of 4,6-Dideoxyfuranoses through the Regioselective and Diastereoselective Oxyfunctionalization of a Dimethylphenylsilyl-Substituted Chiral Homoallylic Alcohol

Mutant Lipase‐Catalyzed Kinetic Resolution of Bulky Phenyl Alkyl sec‐Alcohols: A Thermodynamic Analysis of Enantioselectivity

ChemInform Abstract: Lipase‐Catalyzed Kinetic Resolution of Z‐Configured Homoallylic Alcohols.

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