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Natural product synthesis racemic alcohols, kinetic resolution

This chapter illustrates the application of lipases and esterases as user-friendly biocatalysts in (i) desymmetrization of prochiral or meso-diols and diacetates, (ii) kinetic resolution of racemic alcohols, and (iii) preparation of enantiopure intermediate(s) from a mixture of stereoisomers by enzymatic differentiation. All the examples were taken from our own works in natural products synthesis. [Pg.587]

Kinetic resolution of secondary allylic alcohols by Sharpless asymmetric epoxidation using fert-butylhydroperoxide in the presence of a chiral titanium-tartrate catalyst has been widely used in the synthesis of chiral natural products. As an extension of this synthetic procedure, the kinetic resolution of a-(2-furfuryl)alkylamides with a modified Sharpless reagent has been used . Thus treatment of racemic A-p-toluenesulphonyl-a-(2-furfuryl)ethylamine [( )-74] with fert-butylhydroperoxide, titanium isopropoxide [Ti(OPr-/)4], calcium hydride (CaHa), silica gel and L-(+)-diisopropyl tartrate [l-(+)-DIPT] gave (S)-Al-p-toluenesulphonyl-a-(2-furfuryl)ethylamine [(S)-74] in high chemical yield and enantiomeric excess . Similarly prepared were the (S)-Al-p-toluenesulphonyl-a-(2-furfuryl)-n-propylamine and other homologues of (S)-74 using l-(+)-D1PT. When D-(—)-DIPT was used, the enantiomers were formed . ... [Pg.120]

Synthesis of (-)-aurantioclavine, (-)-lobeline, and (-)-sedamine Several alkaloids contain chiral benzyl alcohol residues and they can be prepared via oxidative kinetic resolution of the corresponding racemic mixtures. Examples of the application of Pd(II)-(—(-sparteine catalyst to this class of natural products were provided by Stoltz et al. " that proposed alternative synthesis for (—(-aurantio-clavine 133, which is an ergot alkaloid that contains a tricyclic ring system and a single stereocenter. The... [Pg.1062]


See other pages where Natural product synthesis racemic alcohols, kinetic resolution is mentioned: [Pg.276]    [Pg.1066]    [Pg.531]    [Pg.206]    [Pg.120]    [Pg.145]    [Pg.531]    [Pg.565]    [Pg.37]    [Pg.251]    [Pg.213]    [Pg.1047]    [Pg.1072]   


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Alcohols kinetic resolution

Alcohols natural products

Alcohols production

Alcohols synthesis

Kinetic products

Kinetics alcohol

Kinetics synthesis

Natural products, synthesis

Natural racemate

Product resolution

Racemate kinetic

Racemate resolution

Racemates production

Racemates synthesis

Racemic alcohols, kinetic resolution

Racemic kinetic resolutions

Racemic products

Racemic resolution

Racemic synthesis

Racemization alcohols

Racemization kinetics

Racemization resolution

Resolution synthesis

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