Cis- -Carveol

Materials anhydrous TBHP was made by extracting a 70% TBHP solution (in water) in chlorobenzene and drying over 3A molecular sieves, to result in a 5 M solution. Cyclohexene and cyclooctene were distilled and were passed through a column of basic alumina before use. Vanadyl(IV) sulphate hydrate, Salen (N,N -bis(salicylidene)-ethylenediimine), 1,2,-dichloro-ethane (DCE), dichloromethane (DCM), acetone, and acetonitrile were reagent grade and used as received. (-) Carveol was purchased as a 1.48 1 mixture of trans- and cis-carveol and used as such. Cumylhydroperoxide was purchased as a 80% solution in cumene and used as received. 

As a test reaction a mixture of cis- and trans-carveol was oxidized with TBHP. Analogous to what has previously been observed for compounds like geraniol and linalool, epoxidation was fast and selective (reaction 8). Trans-carveol was converted only to the corresponding epoxide, whereas cis-carveol gave a mixture of cis-epoxide and carvone. 

By using whole cells of Rhodococcus erythropolis DCL14, a racemic mixture of (-)-carveol was converted to (-)-carvone and (-)-cis-carveol (Fig. 16.2-39). The system was optimized using the two-liquid concept, in which a second organic phase serves as substrate and product reservoir. (-)-Carvone is an important flavor compound. 

The use of a two-liquid phase system consisting of a 1 1 mixture of phosphate buffer and dodecane resulted in an increase of the initial (-)-trans-carveol conversion rate by 70% (to 26 nmol per minute and per mg protein). The production was increased from 4.3 to 208 pmol (-)-carvone formed per mg protein as compared to the aqueous system. A simple downstream process consisting of phase separation, methanol extraction, evaporation, and separation of (-)-cis-carveol and (-)-carvone over a silica gel column, was developed. 

CAS 2102-59-2 EINECS/ELINCS 218-270-5 Synonyms cis-Carveol (1R-cis)-2-Methyl-5-(1-methylvinyl) cyclohex-2-en-1-ol Uses Fragrance in cosmetics... 

Newly isolated unidenti ed red yeast, Rhodotorula sp., converted (+)-limonene (68) mainly to (+)-limonene-l,2-tran5 -diol (71a), (-r)-trfl 5 -carveol (81a), (+)-cis-carveol (81b), and (+) carvone (93 ) together with (+) limonene-1,2 cis-diol (71b) as minor product (Noma and Asakawa, 2007b) (Figure 19.36). 

Nishimura, H., S. Hiramoto, J. Mizutani, Y. Noma, A. Furusaki, and T. Matsumoto, 1983b. Structure and biological activity of bottrospicatol, a novel monoterpene produced by microbial transformation of -) -cis-carveol. 47 2697 2699. 

FIGURE 14.83 The Metabolic pathways of ci -carveol (81b ) by Pseudomonas ovalis, strain 6-1 (Modified from Noma, Y, 1977. Nippon Nogeikagaku Kaishi, 51 463-470) and Streptomyces bottropensis SY-2-1 and other microorganisms (Modified from Noma, Y. et al., 1982. Agric. Biol. Chem., 46 2871-2872 Nishimura, H. et al, 1983a. Proc. 27th TEAC, pp. 107-109). 

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