CHEMICAL REACTIVITY OF SESBAGRANDIFLORAIN: THEORETICAL STUDY

• Main Author: Nurhayati, Mita
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/41386
• Institution: Institut Teknologi Bandung

Benzofuran derivati ve substances are potential for therapeutic agents because its bioactivity. Benzofuran derivative can be found in natural product isolation or made syntheticaly. Recently, benzofuran derivative is found from stem bark isolation of Sesbania grandiflora using ethyl acetate. To develop sesbagrandiflorain as another kind of potential therapeutic agents, the reactivity of molecule is necessary to be known. In this research , theoretical study about sesbagranditlorain and it's reactivity is conducted using computational method. Geometry optimization is conducted uing HF/6-31 g method. The results show that the structure of sesbagrandi tlorain is changed by solvent. The substituents of aryl benzofuran main chain are significantly changed. Global reactivity can be calculated by si ngle point energy using B3L YP/6-31 g, B3L YP/6-31 ++g, B3L YP/6-311++g, B3L YP 6-311++g(d), and M06/6-31 g without solvent, and with water and methanol as solvent. Global reactivity descriptors that is calculated are ionizating energy, electron affinity, electronegativity, and hardness. Based on global reactivity descriptor calculation, sesbagrandiflorain tend to more reactive in water. Local reactivity (Fukui indices) is caJculated using a lot of theory without or with water and methanol as solvent. Based on the calculation, the functional group that tend to attacked by a nucleophilic is aldehyde functional group. Carbon that having -OH and -OCH3 functional group tend to attack electrophile. Fukui indices for radical attack is small, means that the molecule is less reactive to some radical attack. Single point calculation is conducted to nitration reaction that involve sesbagranditlorain in certain position. Single point calculation is conducted using geometry optimization result. It use DFT method with hybrid functional B3LYP/6-31Jg++(d). There is five position that can be substituded by -N02 . The five positions show the similiar nitration reaction energy diagram trend. The solvents tend to stabilize nitration reaction intermediate and product of sesbagrandiflorain.