Kajian Reaksi Alkilasi Dihidropirimidinon Menggunakan Natrium Hidroksida

Masitoh, Heni (2025) Kajian Reaksi Alkilasi Dihidropirimidinon Menggunakan Natrium Hidroksida. Masters thesis, Institut Teknologi Sepuluh Nopember.

Text 6004231008-Master_Thesis.pdf Restricted to Repository staff only until 1 April 2027. Download (4MB) | Request a copy

Abstract

Senyawa-senyawa berkerangka dihidropirimidinon berperan penting dalam bidang kimia organik dan medisinal. Modifikasi struktur dihidropirimidinon termasuk insersi gugus alkil melalui reaksi alkilasi terus dikembangkan akibat keterbatasan dalam yield produk, reagen alkil halida, kondisi reaksi, dan selektivitas. Tujuan penelitian ini adalah melaporkan alkilasi dihidropirimidinon dengan beberapa alkil halida menggunakan basa natrium hidroksida (NaOH). Senyawa dihidropirimidinon berupa etil 4-fenil-6-metil-2-okso-1,2,3,4 tetrahidropirimidin-5-karboksilat 4 diperoleh dari reaksi antara benzaldehida 1, urea 2, dan etil asetoasetat 3 dengan yield 56%. Model reaksi alkilasi senyawa 4 dilakukan dengan benzil klorida 5a menggunakan NaOH bervariasi (0,7 mmol, 1,4 mmol, 2,8 mmol, 4,2 mmol), perlakuan yang berbeda terhadap campuran reaksi, dan dalam waktu reaksi 3 jam dan 12 jam. Alkilasi senyawa 4 oleh benzil klorida 5a dengan NaOH 1,4 mmol dan 2,8 mmol masing-masing menghasilkan senyawa etil dan 1-benzil-6-metil-2-okso-4-fenil-1,2,3,4-tetrahidropirimidin-5-karboksilat 6a etil 1,3-di-benzil-6-metil-2-okso-4-fenil-1,2,3,4-tetrahidropirimidin-5 karboksilat 7 dengan yield yang sama sebesar 58% dan 70%. Perlakuan yang berbeda terhadap reaksi yang sama (NaOH 1,4 mmol) memberikan produk senyawa 6a dengan yield yang lebih rendah (43%). Waktu reaksi alkilasi selama 12 jam dengan NaOH 1,4 mmol memberikan produk senyawa 6a dengan yield 43% yang lebih rendah dibandingkan dengan waktu 3 jam. Alkilasi senyawa 4 dengan 1 bromo-3-kloropropana 5b, 3,3-dimetilalil bromida 5c, dan geranil bromida 5d menggunakan NaOH 1,4 mmol selama 3 jam menghasilkan senyawa etil 1-(3 kloropropil)-6-metil-2-okso-4-fenil-1,2,3,4-tetrahidropirimidin-5-karboksilat 6b, etil 6-metil-1-(3-metilbut-2-en-1-il)-2-okso-4-fenil-1,2,3,4-tetrahidropirimidin-5 karboksilat 6c, dan etil 1-(3,7-dimetil-okta-2,6-dien-1-il)-6-metil-2-okso-4-fenil 1,2,3,4-tetrahidro-pirimidin-5-karbok-silat 6d masing-masing dengan yield sebesar 67, 55, dan 30%. Struktur senyawa hasil sintesis diidentifikasi dengan spektrometer inframerah dan NMR serta analisis massa.
=================================================================================================================================
Dihydropyrimidinone framework compounds play an important role in the fields of organic and medicinal chemistry. Structural modifications of dihydropyrimidinones including the insertion of alkyl groups through alkylation reactions continue to be developed due to limitations in product yields, alkyl halide reagents, reaction conditions and selectivity. The purpose of this study is reports the alkylation of dihydropyrimidinone with several alkyl halides using sodium hydroxide (NaOH) base. The dihydropyrimidinone compound in the form of ethyl 4-phenyl-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate 4 was obtained from the reaction between benzaldehyde 1, urea 2, and ethyl acetoacetate 3 with a yield of 56%. The alkylation reaction model of compound 4 was carried out with benzyl chloride 5a using varying NaOH (0,7 mmol, 1,4 mmol, 2,8 mmol, 4,2 mmol), different treatments for the reaction mixture, and reaction times of 3 hours and 12 hours. Alkylation of compound 4 by benzyl chloride 5a with 1,4 mmol and 2,8 mmol NaOH respectively produced the ethyl compound 1-benzyl-6 methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine- 5-carboxylate 6a and ethyl 1,3-dibenzyl-6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydro-pyrimidine-5-carboxy late 7 with the same yield of 58% and 70%. A different treatment of the same reaction (NaOH 1,4 mmol) gave the product compound 6a with a lower yield (43%). An alkylation reaction time of 12 hours with 1,4 mmol NaOH gave the product compound 6a with a yield of 43% which was lower than the time of 3 hours. Alkylation of compound 4 with 1-bromo-3-chloropropane 5b, 3,3-dimethylallyl bromide 5c, and geranyl bromide 5d using 1.4 mmol NaOH for 3 hours produced the ethyl compound 1-(3-chloropropyl)-6-methyl-2-oxo-4-phenyl-1,2,3,4 tetrahydro-pyrimidine-5-carboxy-late 6b, ethyl 6-methyl-1-(3-methylbut-2-en-1 yl)-2-oxo-4-henyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate 6c, ethyl 1-(3,7dimethylocta-2,6-dien-1-yl)-6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimi din-5-carboxylate 6d, respectively with yields of 67, 55, and 30%. The structure of the synthesized compound was identified using infrared spectrometry and NMR and mass analysis.

Item Type:	Thesis (Masters)
Uncontrolled Keywords:	alkylation, dihydropyrimidinone, natrium hydroxide, alkilasi, dihidropirimidinon, natrium hidroksida
Subjects:	Q Science > QD Chemistry > QD251.2 Chemistry, Organic. Biochemistry
Divisions:	Faculty of Natural Science > Chemistry > 47101-(S2) Master Thesis
Depositing User:	Heni Masitoh
Date Deposited:	06 Feb 2025 04:38
Last Modified:	06 Feb 2025 04:38
URI:	http://repository.its.ac.id/id/eprint/118363

Actions (login required)

View Item