Synthesen in der Carotinoid‐Reihe. 14. Mitteilung Synthese von β‐Apo‐12'‐carotinal (C₂₅)

Abstract

Abstract Using the enol benzoate or enol ether of methylmalonaldehyde and 1, l‐diethoxy‐2‐methylpent‐2‐en‐4‐yne as intermediates for polyene syntheses a number of polyenes have been synthesized. From β‐C 19 ‐aldehyde, β‐apo‐12′‐carotenal(C 25 ) has been prepared via the 15,15′‐dehydro compound and found to be identical with one of the oxidation products of β‐carotene previously obtained by K ARRER . The preparation of key intermediates for the lycopene and canthaxanthin synthesis has been improved.