Self-Assembly of Anthranilamide Derivatives as Organogels

SITTI MENTARI A A, Dr. Tutik Dwi Wahyuningsih, M.Si.; Dr. Endang Astuti, M.Si.

2019 | Skripsi | S1 KIMIA

Reaksi pembukaan cincin isatoik anhidrida dengan alkilamina untuk mensintesis benzamida yang selanjutnya diasetilasi untuk menghasilkan benzamida terasetilasi telah dilakukan. Sifat-sifat self-assembly, atau perakitan mandiri, dari benzamida terasetilasi diuji dalam 25 sistem pelarut berbeda. Struktur dan sifat mekanik juga dianalisa melalui spektroskopi dan reologi. Sintesis benzamida dilakukan dengan menambahkan n-alkilamina, yaitu desilamina, dodesilamina, dan tetradesilamina¸ ke dalam larutan isatoik anhidrida dalam air pada suhu ruang selama 8 jam untuk menghasilkan 2-amino-N- desilbenzamida (3a), 2-amino-N-dodesilbenzamida (3b), and 2-amino-N- tetradesilbenzamida (3c). Selanjutnya, reaksi asetilasi dilakukan dengan menambahkan anhidrida asetat dan trietilamina ke dalam campuran 3a-c dalam diklorometana dan sistem atmosfer gas argon selama 12 jam menghasilkan benzamida terasetilasi: 2-asetamido-N-desilbenzamida (4a), 2-asetamido-N- dodesilbenzamida (4b), and 2-asetamido-N-tetradesilbenzamida (4c). Elusidasi struktur dilakukan dengan spektroskopi 1H-NMR, 13C-NMR, dan FTIR. pengujian sifat self-assembly, struktur dianalisis melalui spektroskopi NMR dan UV-Vis dan sifat mekanik ditentukan menggunakan uji reologi yaitu uji frekuensi dan ketegangan. Hasil percobaan menunjukkan bahwa senyawa 3a, 3b, dan 3c telah berhasil disintesis dengan rendemen berturut-turut sebesar 92, 94, dan 97%. Reaksi asetilasi terhadap senyawa 3a-c juga berhasil dilakukan dan diperoleh produk 4a, 4b, dan 4c dengan rendemen berturut-turut sebesar 77, 89, dan 95%. Hasil analisis membuktikan bahwa senyawa 4a dalam 30% DMSO merupakan gel yang paling stabil meskipun sifat kekakuannya tidak menunjukkan hasil terbaik.

A ring-opening reaction of isatoic anhydride with alkylamines to form benzamides followed by an acetylation reaction was carried out to synthesise acetylated benzamides. The self-assembling properties of the acetylated benzamides were tested in 25 solvent systems. Their structural and mechanical characteristics were analysed through concentration-dependent spectroscopy and rheology, respectively. The synthesis of benzamides was done by adding an n-alkylamine, i.e. decylamine, dodecylamine, or tetradecylamine, to isatoic anhydride in water at room temperature for around 8 h to produce 2-amino-N-decylbenzamide (3a), 2- amino-N-dodecylbenzamide (3b), and 2-amino-N-tetradecylbenzamide (3c). A subsequent acetylation reaction by adding acetic anhydride and triethylamine to 3a- c in DCM under inert Ar atmosphere for 12 h produced the acetylated benzamides: 2-acetamido-N-decylbenzamide (4a), 2-acetamido-N-dodecylbenzamide (4b), and 2-acetamido-N-tetradecylbenzamide (4c). Structure elucidation was done by 1H-NMR, 13C-NMR, and FT-IR spectroscopies. After the self-assembly tests, their structural characteristics were analysed through concentration-dependent 1H-NMR and UV-Vis spectroscopies and for the best gels formed in the self-assembly test, their mechanical properties were tested through rheology in the frequency and strain sweep tests. From the research done, it was found that the synthesis of 3a, 3b, and 3c had been successfully done with yields 92, 94, and 97%, respectively. The acetylation of 3a-c to form 4a, 4b, and 4c had also been successfully done with yields of 77, 89, and 95%, respectively. Through the analysis, it was found that 4a in 30% DMSO was the most stable gel though not as stiff as the rest.

Kata Kunci : anthranilamide, isatoic anhydride, organogels, self-assembly