CHAPTER 4
RESULT AND DISCUSSION
4.1 Preparation of Bis-Thiourea Derivatives
The mixture of heptanoyl chloride and ammonium thiocynate with 1,4-phenylene diamine appeared as homogeneous solution. White precipitate was formed immediately when the solution was filtered into the beaker containing ice cubes. Then, the precipitate was filtered again and rinsed by ethanol before being dried in the desiccator. The physical data of the synthesized bis-thiourea derivatives are shown in Table 4.1.
Table 4.1: Physical data of synthesized thiourea derivatives
Compound Molecular formula Melting point (°C) % yield Color
1,4-bis
(N’- …show more content…
In a fundamental, there are three major criteria of N-H stretching frequencies (University of Missouri–St. Loui, 2013)
First, the force constant for N-H stretching is stronger, second, there is a larger dipole moment associated with the N-H bond, and finally, the N-H bond is usually involved in hydrogen bonding. The stronger force constant leads to a higher frequency for absorption. The N-H stretching frequency is usually observed from 3100-3500 cm-1. Therefore, the synthesized 1,4-bis(n’-heptanoylthioreido)benzene shows the stretching of N-H peak.
Table 4.2: Absorption frequencies of the functional group
Functional group Frequencies (cm-1)
N-H 3100-3500
C=O 1670-1820
C=S 1210-1250
C-N
RESULT AND DISCUSSION
4.1 Preparation of Bis-Thiourea Derivatives
The mixture of heptanoyl chloride and ammonium thiocynate with 1,4-phenylene diamine appeared as homogeneous solution. White precipitate was formed immediately when the solution was filtered into the beaker containing ice cubes. Then, the precipitate was filtered again and rinsed by ethanol before being dried in the desiccator. The physical data of the synthesized bis-thiourea derivatives are shown in Table 4.1.
Table 4.1: Physical data of synthesized thiourea derivatives
Compound Molecular formula Melting point (°C) % yield Color
1,4-bis
(N’- …show more content…
In a fundamental, there are three major criteria of N-H stretching frequencies (University of Missouri–St. Loui, 2013)
First, the force constant for N-H stretching is stronger, second, there is a larger dipole moment associated with the N-H bond, and finally, the N-H bond is usually involved in hydrogen bonding. The stronger force constant leads to a higher frequency for absorption. The N-H stretching frequency is usually observed from 3100-3500 cm-1. Therefore, the synthesized 1,4-bis(n’-heptanoylthioreido)benzene shows the stretching of N-H peak.
Table 4.2: Absorption frequencies of the functional group
Functional group Frequencies (cm-1)
N-H 3100-3500
C=O 1670-1820
C=S 1210-1250
C-N