| 摘要 |
Process for preparing polyene aldehydes of formula where R1 from left to right = H, Me alternately; R2 starting from the bond -C C- = Me, H alternately m = 0,1,2,3, n = 0,1,2,3; m + n = at least 1 and the dotted bond may be hydrogenated. by reacting a compound of formula (II) where Ar = aryl group X- = is an anion with at least an equimolar amount of a compound of formula O=CH-( :CH)m-C triple bond C.(CH: )m-CHO in an organic medium in presence of a proton acceptor. New process for compounds I which are inters for other polyenes or useful as cosmetic and foodstuff colouring agents. |
