ESTERIFICATION OF CINNAMIC ACID WITH OCTANOLUSING ULTRASONIC WAVE ASSISTED BY COUPLING REAGENT AS ANTIERYTHEMA

Abstract

The n-octyl cinnamate compound, a cinnamate ester, is believed to have antierythema activity.
This compound is naturally present in certain plant species; however, its quantity is limited.
Steglich esterification can be used to produce n-octyl cinnamate, which involves the reaction
of cinnamic acid with n-octanol using n,n'-dicyclohexylcarbodiimide (DCC) as a coupling
reagent. Ultrasonic wave-assisted synthesis was performed to reduce the synthesis time and
increase the yield of n-octyl cinnamate with time variations of 3, 4, and 5 hours at ± 2°C. The
synthesized compounds were characterized by organoleptic properties, solubility, melting
point, TLC, FTIR, and GC-MS tests. The synthetic compound occurred as a white powder,
yielding 10.1% after an optimal duration of 4 hours. The compound was insoluble in distilled
water but soluble in methanol, ethanol, chloroform, ether, and n-hexane. The compound has
a melting range of 135.1-145.4°C, and the TLC results obtained different Rf values than the
initial compound. FTIR test analysis showed the presence of C=C aromatic, C-H aromatic,
C=O ester, C-O ester, C=C aliphatic, and C-H aliphatic group absorption by the n-octyl
cinnamate compound. GC-MS analysis revealed a synthetic retention time of 17.193 minutes
and an abundance of 35.40%. The antierythema activity of the synthesized n-octyl cinnamate
compound was optimal at 100 ppm with a %TE of 1.661, classifying it as an extra protection
category.

Keywords: anti-erythema, esterification, ultrasonic waves, n-octyl cinnamate, time.