Name or write the condensed structural formula for the...

Name or write the condensed structural formula for the following compounds:
(a) cis-2-pentene
(b) 1,6-dichloro-3-hexyne
(c) $\mathrm{BrC} \equiv \mathrm{CBr}$
(d) 1,3 -Benzenediol
(e) $\mathrm{CH}_{2}=\mathrm{CH}_{2} \mathrm{CH}\left(\mathrm{CH}_{3}\right) \mathrm{CH}=\mathrm{CH}_{2}$

Key Concepts

Aromatic Compound Representation

This concept involves understanding the unique structure of aromatic compounds such as benzene and its derivatives. Aromatic compounds are often represented in condensed form with a focus on substituent positions, which is critical for interpreting structures like benzenediol.

Representation of Multiple Bonds

This concept highlights the notation used for multiple bonds in organic molecules. Double bonds (alkenes) and triple bonds (alkynes) are represented by '=' and '?', respectively, in condensed structural formulas, indicating regions of increased electron density and reactivity.

Functional Groups

Functional groups are specific groups of atoms within molecules that confer characteristic chemical reactivities and physical properties. Recognizing groups such as alkenes, alkynes, halogens, and hydroxyl groups is essential for both naming compounds and writing their structural representations.

Stereochemistry

Stereochemistry deals with the three-dimensional arrangement of atoms in molecules, particularly around double bonds or chiral centers. In compounds like cis-2-pentene, the relative positions of substituents (on the same or opposite sides of a double bond) are crucial for describing the molecule's geometry.

Organic Nomenclature

This concept involves the systematic naming of organic compounds according to established rules (like IUPAC). It provides a way to describe the structure and functional groups present within a molecule by using specific numbers, prefixes, and suffixes, making it possible to deduce the structure from its name.

Condensed Structural Formula

The condensed structural formula is a shorthand notation that represents the structure of a molecule by grouping atoms together to show connectivity without drawing every individual bond. It simplifies complex structures while conveying the types and sequences of atoms present.

Transcript

00:01 Okay, we're asked to give formula or draw the following structures.

00:03 First one is cis 2 -pentine.

00:06 So cis meaning that both the highest priority groups from the same side of the double bond, and pencine is 5 carbons, or pencine is 5 carbons.

00:16 I think it's easiest to draw the alken first, the 2 -carbon al -alkeen first, and then put the groups on the other side of the double bond.

00:27 So the al -keens on carbon 2, which means we're going to put a methyl down here, hydrogen here, methyl has more priority of the hydrogen because the carbon is a higher atomic number.

00:42 And as a result, we're going to put the rest of the chain down here because it's cis.

00:47 Three, we need two more carbons.

00:53 Look at that.

00:56 And if we want to give a formula, we have five carbons in total in pencene.

01:01 And looking at the hydrogens, we have three here, four, five, six, seven, and then three at the end.

01:11 So, i have ten.

01:15 Now the next one is one -six -dichloric.

01:18 Or 3 hex line.

01:22 Okay, so the ion ending positive of an al -kind, and it's on carbon of 3.

01:25 We're going to draw the structure first, like in a line.

01:32 Let's see it 3.

01:34 See al -kind.