Following is the \({ }^{1} \mathrm{H}\)-NMR spectrum of compound \(\mathrm{O}\), molecular formula \(\mathrm{C}_{7} \mathrm{H}_{12}\) Compound \(\mathrm{O}\) reacts with bromine in carbon tetrachloride to give a compound with the molecular formula \(\mathrm{C}_{7} \mathrm{H}_{12} \mathrm{Br}_{2}\). The \({ }^{13} \mathrm{C}-\mathrm{NMR}\) spectrum of compound \(\mathrm{O}\) shows signals at \(\delta 150.12,106.43,35.44,28.36\), and \(26.36\). Deduce the structural formula of compound \(\mathrm{O}\).

13C-NMR spectroscopy is a valuable tool in organic chemistry for determining the structures of carbon-containing compounds. By analyzing the carbon-13 NMR spectrum, chemists can deduce the different carbon environments present in a molecule. Each unique carbon environment results in a separate signal at a specific chemical shift, measured in parts per million (ppm).

The chemical shift gives insights into the electronic environment of the carbons. For instance, downfield shifts (higher ppm values) typically indicate carbons bonded to electronegative atoms like oxygen or nitrogen, or those in pi bonds, such as in alkenes or aromatic systems. On the other hand, upfield shifts (lower ppm values) often associate with carbons in saturated environments such as alkanes.

Interpretation involves matching the observed chemical shifts with known reference values for various carbon types. Significant to remember is that the number of signals correlates with the number of distinct carbon environments, helping to piece together the compound's structure.

1H-NMR spectroscopy complements its 13C counterpart by focusing on hydrogen atoms. It provides insights into how many different proton environments exist within a molecule. Just like the 13C-NMR, the 1H-NMR spectrum displays chemical shifts in ppm, which vary depending on the neighboring atoms and the type of chemical bonds.

Chemical shifts toward higher frequencies (downfield), near 6-8 ppm, often signify protons on carbons adjacent to double bonds or aromatic rings. In contrast, protons on saturated carbons resonate at lower frequencies (upfield) typically between 0.5-5 ppm. The area under each signal, known as the integral, reflects the number of protons contributing to that signal.

Coupling patterns, observed as splitting of signals, can further unravel the proximity and number of neighboring hydrogen atoms, giving an even clearer picture of the molecular structure. When interpreting a 1H-NMR spectrum, all these features must be considered to accurately deduce the molecular structure.

Deducing the molecular structure from NMR spectroscopy involves synthesizing the information from both the 13C and 1H spectra. After identifying the number and type of carbon and hydrogen environments, chemists can begin to piece together the puzzle of the molecule's architecture. Structural isomers pose a particular challenge as they may have the same molecular formula but different structural arrangements.

The approach often begins by identifying the core skeleton—determining which carbons form the backbone of the molecule and how they're connected. The presence of functional groups is then inferred from specific chemical shift regions. Lastly, the integration and multiplicity of the 1H signals can help locate the relative positioning of protons to one another.

Combining these data points allows chemists to construct a reasonable structure that accounts for the molecular formula and the observed NMR characteristics, eventually deducing the most probable chemical structure for the compound in question.

Alkene bromination is a specific type of halogenation reaction where bromine (Br₂) adds across the double bond of an alkene, resulting in a vicinal dibromide. This reaction occurs typically in a non-polar solvent such as carbon tetrachloride (CCl₄).

During the reaction, the pi electrons of the alkene attack the bromine molecule causing heterolytic fission of the Br-Br bond. A cyclic bromonium ion intermediate forms, and then nucleophilic attack by another bromide ion results in the vicinal dibromide product. It is stereospecific, meaning that the two bromine atoms will add to opposite faces of the double bond, producing a trans product when the alkene is cyclic.

Understanding this reaction is crucial when deducing structures, as observing a new molecular formula featuring additional bromine atoms indicates that a bromination reaction has occurred, revealing the existence and position of the alkene within the original molecule.