Synthesis of a Novel Tocopherol/Carotenoid Derivative
The goal of this work is the synthesis of a tocopherol/carotenoid hybrid
derivative (1, figure II). The novel derivative is believed to exhibit
synergistic antioxidant effects between its chromanol and polyene consituents.
The synthesis of 1 was completed up to and including the
immediate precursor 12.
Commercially avaliable Trolox (7) was reduced by Red-Al® to 8
(step a) in 95% yield. Chromanol aldehyde 9 was formed by Swern
oxidation of 8 in 65% yield (step b). Wittig reaction between 9 and
phosphonium salt 10 afforded 11 in 33% yield and varying cis : trans
ratio (step c), and subsequent elongation produced 12 (14% yield, step
d). The Wittig reactions were performed with reflux and microwave
Various attempts at protecting the phenolic group in intermediate
8 by silylation or benzylation did only lead to formation of 8B.
Oxidation of 8 by the Dess-Martin oxidation formed the unexpected
quinone-like derivative 27. Efforts to protect the phenolic group in intermediate
9 by benzoylation and silylation only produced 9A, found
to be unsoluble in all common laboratory solvents.
Place, publisher, year, edition, pages
Institutt for kjemi , 2012. , 176 p.
ntnudaim:6705, MKJ Kjemi, Organisk kjemi
IdentifiersURN: urn:nbn:no:ntnu:diva-16805Local ID: ntnudaim:6705OAI: oai:DiVA.org:ntnu-16805DiVA: diva2:536474
Partali, Vassilia, ProfessorSliwka, Richard