
TY  - JOUR
A1  - Whitfield, FB 
A1  - Sugowdz, G 
T1  - The 6-(but-2'-enylidene)-1,5,5-trimethylcyclohex-1-enes: Important volatile constituents of the juice of the purple passionfruit <I>Passiflora edulis</I>
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1979
VL  - 32
IS  - 4
SP  - 891
EP  - 903
KW  - 
UR  - https://doi.org/10.1071/CH9790891 
N2  - Two important flavour components of the juice of the purple passionfruit Passflora edulis (Sims) have been shown by g.l.c., mirco-reaction g.l.c., u.v., i.r., N.M.R., mass spectrometry, and by synthesis to be (6E,2'E)- and (6Z,2'E)-6-(but-2'-enylidene)-1,5,5-trimethylcyclohex-1-ene (2a) and (2b). Evidence is also reported for the presence in this juice of trace amounts of the stereoisomers (2c,d). The 6-(but-2'-enylidene)-1,5,5-trimethylcyclohex-1-enes are very susceptible to oxidation and, in dilute acetic acid solution, are rapidly converted into 'ionene', 1,1,6-trimethyl-1,2,3,4-tetrahydro- naphthalene (10). The significance of this reaction in the loss of flavour during pasteurization of passionfruit juice is discussed. 
ER  -

