Jose David, P; Dr.Paul, Vatakencherry A(Cochin University Of Science And Technology, February 17, 1989)
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Abstract:
In the present work different new approaches for the synthesis
of Vitamin A are investigated. In these synthetic schemes, all the
twenty carbon atoms of the target molecule are derived either fully
from components isolated from common essential oils or partially from
commercially available materials. By retrosynthetic analysis, Vitamin A molecule can be disconnected into a cyclic and a linear unit. Different methods for the synthesis of the linear and the cyclic components are described.
The monoterpenes, geraniol and citral, major constituents of
palmarosa and lemongrass oils, have the required basic carbon framework
for consideration as starting materials for the synthesis of Vitamin A.
The potential of these easily available naturally occurring compounds
as promising starting materials for Vitamin A synthesis is demonstrated.
Organoselenium and organosulfur mediated functional group transformations
for the synthesis of the functionalised conjugated C10 linear components
(ie., the dimethyloctatriene derivatives) are reported. The classical
approaches as well as the attempted preparation of cyclic C10 and C13
units employed in the present study as intermediates for Vitamin A
synthesis are described. The utility of commercially available materials namely 2-acetylbutyrolactone and levulinic acid in -the preparation of C5 intermediates for Vitamin A synthesis is demonstrated.
Description:
Department Of Applied Chemistry
Cochin University Of Science And Technology