Discussion By analyzing the results and data from the spectra above, the structure of the molecular formula C6H12O2 can be established. The first step toward identifying the structure of an unknown compound is to calculate the degree of unsaturation, and in this case it was calculated to be 1. Since there was only 1 degree of unsaturation, a C=O bond or a C=C bond was immediately predicted, and this prediction was tested by analyzing the IR spectrum. Because there was a peak at 1742 cm-1, it was determined that the 1 degree of unsaturation was due to a C=O bond. Also, the peaks on the IR only show readings at 2983 cm-1, which denote Csp3-H bonds, and no peaks designating Csp2-H bonds. The last key functional group exhibited in the IR spectrum was a C-O stretch at 1242 cm-1. These findings allowed me to realize the functional groups in the molecule but left me with no information regarding how the molecule was connected. After the functional groups are determined from the IR spectrum, 1H-NMR should be used so that clues to the connectivity of the molecule can be uncovered. After analyzing the data from …show more content…
The molecular weight of C6H12O2 is 116 g/mol. If the fragments labeled as A, B, and C in Figure 6 were removed from the molecule, the resulting molecular weight would be 73 g/mol which coincides with the data presented in Table 4. Similarly, if every fragment except for the carbonyl group were removed from the molecule, the resulting molecular weight would be 43 g/mol. This molecular weight corresponds with the data exhibited in Table 4. After careful examination of each spectra, the molecular structure in Figure 1 was confirmed to be correct. Without utilizing each of the spectra, certain aspects of the molecular structure cannot be predicted. When all of the spectra are observed together and in a correct manner, the accurate molecular formula can be found
3. The IR spectrum of the starting material shows a medium/strong C-O bond at around 1500cm-1, also the starting material shows a strong C-H bond at around 3000cm-1 and another medium C-H bond at 2865cm-1 indicating an aldehyde group whereas the product does not. The IR spectrum of the product shows a two weak broad O-H peaks at around
- The C-H bonds in this structure are shown at 1444 and 1368cm-1. These two bands indicate the two different types of C-H bends that occur on the molecule. One is that of the alkene and the other is that of the several alkanes on the molecule.
There are four main regions of IR absorptions: region 4000 – 3000 cm-1 corresponds to N-H, C-H and O-H stretching, region 2250- 2100 cm-1 is triple-bond stretching , region 2000- 1500 cm-1 is double bonds and the region below 1500 cm-1 is the fingerprint region where a variety of single bonds are absorbed.3 The chromic acid test is a test for oxidizability and gives a positive result for primary and secondary alcohols as well as aldehydes2. A positive result in the chromic acid test is indicated by a color change and the formation of a precipitate. Tertiary alcohols give negative results for the chromic acid test since there must be a hydrogen present on the alcoholic carbon for oxidation to occur. The 2,4 DNP test, tests for a carbonyl and is therefore a dependable test for aldehydes and ketones. Finally, 13C NMR spectroscopy is a test to determine the structure of a compound. 13C NMR detects the 13C isotope of carbon. Each carbon has a different chemical shift. A carbon’s chemical shift is affected by the electronegativity of nearby atoms. Carbons that are bonded to highly electronegative atoms resonant downfield because the electronegative atom pulls electrons away from the nearby carbons and cause those carbons to resonant downfield1 (John McMurry, 2008). A general trend is that sp3-hybridized carbons absorb from 0 to 90 ppm, sp2-hybridized carbons resonant between 110
Overall, the experiment went smoothly. Our product’s identity and purity was tested by calculating the density, an alkene test using Bromine Water, and conducting both an IR and a H-NMR spectra. The first test that was conducted was comparing densities between our product and the known density of Limonene. From our data, our product had a density of 0.815 g/mL, which is only 0.027 g/mL off from Limonene’s known density of 0.842 g/mL. Our density may even be closer due to the inaccuracy of having less than one millimeter of product.
If the IR spectra showed that it was an alcohol, Jones Test and Lucas Test can be used. If the IR spectra showed that it was either an aldehyde or ketone, we can use the DNP Test, Jones Test, and Tollens test, to determine which functional group is in the unknown. The IR Spectra can distinctively show the unknown as an alcohol, but cannot distinctively distinguish between aldehyde and ketone, because aldehyde and ketones have similar characteristic absorbances. Therefore, to distinguish between aldehyde and ketone, further chemical tests are needed. In the IR Spectra of unknown #305, it indicated that it was most likely an alcohol, due to the O-H peak at
What are the functional groups on this molecule? What is the R group to which they are attached? Is the R group hydrophilic or hydrophobic?
Structural-wise, it is a hexose that occurs in the nature in a D form and has 16 stereoisomers. It has been isolated for the first time by Andreas Marggraf in 1747 (Martini 2014).
The Relative Formula Mass of an Unknown Acid Table of contents 1.1 Aim of the experiment 2 1.2 Introduction 2 1.3 Equipments and apparatus 2 1.4 Safety precautions 2 2.1 Procedure 3 2.2 Apparatus setup 3 2.3 Analysis 4 3.1 Implementing
The sulfonyl bound benzene (C8-C13) ring forms dihedral angles of 35.5(1)o and 65.6(1)o respectively, with the 2-formylpheneyl (C1-C6) and fluorophenyl (C18-C23) rings. The dihedral angle between fluorophenyl(C18-C23) and 2-formylphenyl(C1-C6) ring is 44.0(1)o. The structural parameter of MFMSF conforms to those reported for similar structure [31]. Fluorine atom F1 is deviated by -0.003(2) Å from the attached benzene ring. The hydrogen bond geometry for MFMSF is listed in Table.2. The molecular structure is stabilized by intramolecular C–H…π interaction between a sulfonyl-bound phenyl H9 atom and a fluorophenyl(C18-C23) ring with a C9–H9…Cg separation of 2.66Å, where Cg is the centroid of the C18-C23 fluorophenyl ring. Also, the molecular conformation is stabilized by weak intramolecular C9–H9...O3, C7–H7...N1 and C17–H17...O5 hydrogen bonds, each generates S(5) ring motifs [32]. In the crystal, four molecules are related by two intermolecular C10–H10…O1i and C25–H25A…O2ii hydrogen bonds, generating ring motifs [32] to form a two dimensional supramolecular network along [110] direction (Fig. 2; Symmetry codes as given in
This molecule also exhibit weak pi interaction (C9••••C14 = 3.275 Å) between ring C and A of neighbouring
This oxygen atom has 4 atoms bonded to it with two lone pairs making it’s molecular shape linear. The similarities in these two molecular structures are that they both are composed of carbon, oxygen and hydrogen. At least one of their central atoms has the tetrahedral shape and also a linear shape. Both of the oxygen atoms in each structure are the atoms with the lone pairs. The differences between the two structures are that the isopropanol molecule has more bonds than the acetic acid.
For this investigation, it is necessary to use a piece of software to accurately model the molecule and measure bond angles. This should provide the data necessary to ascertain
When using nuclear magnetic resonance spectrometry, I had unknown A. With this unknown, I had two peaks on my CNMR which told me I had one carbon on both sides of the line symmetry. Also, on my HNMR I had one peak with a multiplicity of six, therefore, I had six hydrogens. Using this information I was able to conclude that my unknown as was 2-propanone.
I have developed a broad knowledge of modern organic chemistry and synthetic methods as well as I have gained practical experience with a wide range of bioanalytical techniques and NMR spectroscopic methods for characterizing biomolecules and biopolymers, involving the concepts and methodologies of structure-based molecular design as well as method development for structure elucidation. I have pursued my research in multiple CUNY research groups that focus on materials science, photonics technologies, structural biology, and magnetic resonance spectroscopy. I have conducted collaborative studies with the plant biology laboratory
We can see that the structural formula of a carboxylic acid can be written two ways. On the left (1), it shows all the carbon, hydrogen and oxygen bonds, while on the right (2), the carbon atom is represented by a