Question

The correct IUPAC name of the following compound is Cc1cccc(C)c1 (A) 2,4 -dimethyl cyclohexa- 1,4 -diene (B) 1,5 -dimethyl cyclohe \(\mathrm{xa}-1,5\)-diene (C) 1,3 -dimethyl cyclohexa-1,3-diene (D) None of these

Short answer

The correct IUPAC name of the given compound is 1,3-dimethyl cyclohexa-1,2-diene, which does not match any of the given options. Therefore, the answer is (D) None of these.

Step-by-step solution

Identify the compound structure and carbon numbering

The given compound is shown by the SMILES notation (Cc1cccc(C)c1). In simplified terms, we can represent the compound as a cyclohexane ring with two methyl groups attached to it. The compound has a double bond in the ring, making it a cyclohexene. We can number the carbons in the ring in a way that the double bond gets the lowest possible numbers, and the substituents (here, the methyl groups) also get the lowest possible numbers.

Assigning substituents and double bond position

Here, we have two methyl groups as substituents on the cyclohexene ring. In order to assign the lowest possible numbering to the substituents and the double bond, we start numbering from one double bond carbon and proceed in the direction which gives the substituent carbons as lower numbers. This way, we can label the carbons as 1, 2, 3, 4, 5, and 6 in a clockwise manner.

Determine the positions of the substituents

Upon numbering the carbons, we find that the methyl groups are attached to the carbons 1 and 3. Also, this numbering assigns the double bond position to 1,2. Therefore, the compound can be named as 1,3-dimethyl cyclohexa-1,2-diene.

Match the name with the given options

Now, let's match the obtained IUPAC name with the given options: (A) 2,4 -dimethyl cyclohexa- 1,4 -diene (B) 1,5 -dimethyl cyclohexa-1,5-diene (C) 1,3 -dimethyl cyclohexa-1,3-diene (D) None of these Based on our IUPAC naming, we can see that the correct name does not match any of the given options. So, the answer is: (D) None of these

Key concepts

Organic Chemistry

Organic chemistry is a branch of chemistry that focuses on the study of carbon-containing compounds, typically featuring carbon skeletons with functional groups attached. This extensive field encompasses everything from hydrocarbons, which consist only of carbon and hydrogen, to complex biomolecules that are integral to life. Understanding organic compounds involves looking at their structure, properties, synthesis, and reactions. Organic chemistry is not just academic; it has practical applications in pharmaceuticals, petrochemicals, food science, and more. In organic chemistry, the systematic naming of compounds is fundamental for clear communication and is standardized by the IUPAC (International Union of Pure and Applied Chemistry) system.

Chemical Structure

Chemical structure refers to both the three-dimensional arrangement of atoms within a molecule and the way in which we represent that arrangement. It's the backbone for understanding a molecule's function and its interaction with other substances. Two primary ways are used to describe the structure of organic compounds: structural formulas, which can range from simple lines indicating chemical bonds between atoms to more complex three-dimensional models, and simplifications, such as SMILES notation, which provide a linear character string. The chemical structure is pivotal in determining the physical and chemical properties of a molecule like reactivity, polarity, phase of matter, color, magnetism, and biological activity.

SMILES Notation

SMILES (Simplified Molecular Input Line Entry System) notation is a way of representing a molecule's structure using a sequence of characters. This system offers a concise, digital-friendly way to convey complex structural information. A SMILES string can describe a molecular structure uniquely, which includes atoms, bonds, branching, and ring structure. It's highly useful for databases, chemical informatics software, and online communication. For example, the SMILES string 'Cc1cccc(C)c1' represents a six-membered benzene ring with two methyl groups, known for its prevalence in organic chemistry.

Cyclohexene

Cyclohexene is an organic chemical compound with the molecular formula \( C_6H_{10} \). It is a simple cycloalkene - a hydrocarbon with a carbon ring and a double bond. This unsaturation means cyclohexene can undergo addition reactions, which make it a chemically reactive species for various synthetic applications. Importantly, in IUPAC naming, the location of the double bond and any substituents on the ring must be specified, as they influence the properties and reactivity of the molecule. Errors in naming can lead to complications in understanding or utilization of the compound, making precise and accurate naming critical in organic chemistry.