Wine lactone

(3S, 3aS, 7aR ) -3,6 -dimethyl -3a, 4,5,7 a- tetrahydro- 3H -1 -benzofuran- 2-one

50-51 ° C ( 3S, 3AS, 7aR ) 58-59 ° C ( 3R, 3AS, 7aR ) 59-60 ° C ( 3S, 3aR, 7aR ) 49-51 ° C ( 3R, 3aR, 7aS )

Template: Infobox chemical / molecular formula search available

The wine lactone is occurring in the wine chemical compound from the group of the bicyclic lactones. It has an intensely sweet and coconut -like odor which is perceptible even in very dilute solutions.

Isomers

Due to the structural make-up of the molecule with three stereocenters, there are four pairs of enantiomers or diastereomers eight.

The actual wine lactone is in the ( 3S, 3aS, 7aR )-configuration, and has the low odor threshold of all isomers on, it is already noticeable at a concentration of from 0.00001 to .00004 nanograms per liter of air.

The very different odor thresholds of the eight isomers in air were determined as follows:

The racemate carries the CAS number 78168-36-2. The isomers can be separated by gas chromatography on a chiral stationary phase.

Representation

(3S, 3AS, 7aR ) - wine lactone and (3R, 3AS, 7aR ) - wine lactone can be prepared from (1R )-trans- Isolimonen.

By a multi-stage reaction, a mixture of ( 3S, 3aS, 6R, 7R, 7aR ) -7- iodo - is 3 ,6- dimethylhexahydrobenzofuran -2 (3H )-one and (3R, 3aS, 6R, 7R, 7aR ) -7 -Iodo -3 ,6- dimethylhexahydrobenzofuran -2 ( 3H)- one was obtained, which can be fractionated by chromatography. The desired isomer can then be reacted with the corresponding diazabicyloundecene wine lactone.