Organic Functional Groups and Molecules - Organic Chemistry

Ethanol (or ethyl alcohol) is characterized as a primary alcohol since there is only one carbon-containing group that is directly attached to the carbon containing the group.

The unsaturation number is equal to the number of rings and pi bonds in a molecule. Here, there are 4 rings and 1 double bond, so the unsaturation number is 5. No formula is needed to calculate unsaturation number when a structural formula is given.

The molecule pictured above is known as an ether because it contains an oxygen atom within the sequence of a carbon chain. (An oxygen atom bonded to two carbons in a carbon chain).

Therefore the correct answer is ether. All other answer choices are carbonyls, meaning that they contain a carbon atom double bonded to an oxygen atom.

Grignard reagents are very strong bases, and therefore can be spoiled by protons. Grignard reagents are so basic in fact that any protic solvent will render them useless. Dimethyl ether is the only non-protic solvent, and is therefore the correct answer.

IV>III>I>II

The most acidic compound is option IV because it contains a carboxylic acid group which is the most acidic organic functional group. Phenols are weak acids. Alcohols in solution are slightly less acidic than water and therefore are slightly basic.

The molecule's longest carbon chain has 6 carbons (thus, "hex-"), and the lack of double bonds makes it an alkane (thus "hexane"). The longest chain is a ring structure (thus "cyclohexane"), and the one branching group is a carbon chain consisting of one carbon and no double bonds (a "methyl" group). Because there are no other functional groups on the molecule there is no need to put a number before the location of the methyl group (thus "methylcyclohexane").

The molecule's longest carbon chain has 5 carbons (thus, "pent"), and the lack of double bonds makes it an alkane (thus "pentane"). The one functional group is a bromine atom attached to carbon number 3 (whether read from left to right or right to left, the bromine is always on carbon number 3). Thus, the molecule is named "3-bromopentane."

The molecule's longest carbon chain has 5 carbons (thus, "pent"), and the one double bond makes it an alkENE (thus "pentene"). The longest chain is a ring structure (thus "cyclopentene"). Because the IUPAC rules automatically assign the location of the first double bond to carbons 1 and 2, there is no need for a number locand.

The molecule's longest carbon chain has 4 carbons (thus, "but"), and the presence of two double bonds makes it an alkENE, more specifically, a diene (thus "butadiene"). Because there is more than one way in which the double bonds can be arranged (between C1-C2 and C2-C3, or between C1-C2 and C3-C4), it's important to place locants indicating the lower-numbered carbon in each double bond.

The molecule's longest carbon chain has 5 carbons (thus, "pent-"), and the carbon-carbon double bond makes it an alkENE (thus "pentene"). The location of the double bond must be specified, and numbering the carbon chain to give the double bond the lowest numbers possible mean that it is numbered from right to left, putting the double bond between carbon 2 and carbon 3. This will put the methyl group on carbon 3.

Regarding stereochemistry, on carbon 2, the higher priority substituent is the methyl group. On carbon 3, the ethyl group is the higher priority. The higher priority substituents are on the same side of the double bond, and therefore the stereochemistry designation is "Z."

The molecule's longest carbon chain has 6 carbons (thus, "hex-"), and the lack of carbon-carbon double bonds makes it an alkANE (thus "hexan-"). The presence of a hydroxyl group makes this molecule an alcohol (thus "hexanol"). The longest carbon chain is a ring structure (thus "cyclohexanol"), and the location of the alcohol group is assumed to be carbon 1 because it's the highest priority functional group on the molecule. The only other substituent is a methyl group, and numbering the carbon chain starting from the one containing the alcohol group and moving toward the methyl group puts the methyl group on carbon 2. Thus "2-methylcyclohexanol."

The molecule's longest carbon chain has 6 carbons (thus, "hex-"), and the presence of three double bonds makes it an alkENE, more specifically, a tri ene (thus "hexatriene"). Because there is more than one way in which the double bonds can be arranged it's important to place locants indicating the lower-numbered carbon in each double bond (1, 3, and 5 in this case).

When naming an organic compound by the IUPAC rules, it's best to first start by identifying the functional groups present.

In this particular case we have:

An Ester in the middle as shown here:

a Methyl group shown here:

and a Butyl group attached to the ester:

Next, we should identify what functional group has the highest priority, as that will form the base name of the compound:

According to IUPAC convention, Carboxylic Acid derivatives including Esters have the highest priority then carbonyls then alcohols, amines, alkenes, alkynes, and alkanes, so in this case the Ester group has the highest priority and therefore makes up the name of the base compound.

Next, we want to number the longest carbon chain with the highest priority functional group with the lowest number. In this case this means we want the carbonyl of the ester to be carbon number #1, so let's start there and number the carbon chain.

You should get something like this:

Notice there are two sixes. The reason why is because there are two possible pathways for the carbon numbering to continue, but both are equivalent meaning no matter what we do there is a 5-methyl group and the carbon chain is 6 carbons long.

Now that we have numbered the carbon chain we can begin our naming.

Let's start with the base name:

According to IUPAC convention the base name for an ester compound is -oate, so in this case we have a hexanoate, which can also be written as hexan-1-oate, but this isn't needed as it as the ester is at carbon 1.

We also have a methyl group at the 5-carbon so in this gives us:

5-methylhexanoate.

However, we aren't done as we haven't named the substituent on the other side of the ester. Let's first count the number of carbons it has. Since this chain has 4 carbons it is a butyl group, as according to IUPAC the chain on the side farthest from carbonyl carbon of the ester is named as a substituent and placed in front of the name of the compound.

This makes our final answer Butyl 5-methylhexanoate.

Now let's go over the other answer choices and why they are wrong:

1) Butyl 5-methylhexenoate is almost correct except for the fact it says Butyl 5-methylhexenoate. The "en" indicates there is an alkene (double bond) in the compound, and since there isn't this can't be the right answer.

2) Butyl 2-methylhex-6-anoate is wrong because the ester group isn't assigned the highest priority. In IUPAC nomenclature you want to assign the highest priority functional group the lowest number possible in the carbon chain.

3) Butyl 2-methylhex-6-enoate is wrong for a mix of the reasons in the previous 2 answers. It says Butyl 2-methylhex-6-enoate in it, and the compound doesn't have an alkene. It also makes the mistake of not making the ester group (the highest priority functional group) have the lowest number possible in the carbon chain, so this can't be right either.

4) 1-butoxy-5-methylhexanone is wrong because it interprets the ester as being a ketone and an ether group instead of an ester.

When naming an organic compound by the IUPAC, it's best to first start by identifying the functional groups present.

In this particular case we have:

A carboxylic acid shown here:

An alkene in the middle of the carbon chain:

A methyl group:

and a ketone towards the end:

Next, we should identify what functional group has the highest priority, as that will form the base name of the compound:

According to IUPAC convention, Carboxylic Acid derivatives including Esters have the highest priority then carbonyls (in this case the ketone) then alcohols, amines, alkenes, alkynes, and alkanes, so in this case the Ester group has the highest priority and therefore makes up the name of the base compound.

Next, we want to number the longest carbon chain with the highest priority functional group with the lowest number. In this case this means we want the carbonyl of the carboxylic acid to be carbon number #1, so let's start there and number the carbon chain.

You should get something like this:

Now that we have numbered the carbon chain we can begin our naming.

Let's start with the base name:

According to IUPAC convention the base name for an carboxylic acid compound is -oic acid, so in this case we have a decanoic acid, which can also be written as decan-1-oic acid, but this isn't needed as it as the carboxylic acid is at carbon 1.

Next notice that we have an alkene that's part of the main chain, since it is part of the main chain we include it in the base name, so we must change our name from decanoic acid to dec**-4-en**oic acid because the lowest it can be numbered is #4, however since the highest priority groups on the alkene are facing opposite to each other it is an E (Entgegen) alkene, so we can name it (4E)-decenoic acid

We also have a methyl group at carbon 5. This gives us:

(4E)-5-methyldecenoic acid.

Finally we have a ketone as a substituent, and a ketone as a substituent is called an oxo, so it becomes 9-oxo.

Now we must order our substituents alphabetically. Thus it becomes

(4E)-5-methyl-9-oxodecenoic acid which is our final answer.

Now let's go over the wrong answers:

1. (4E)-9-oxo-5-methyldecenoic acid is wrong because the substituents aren't ordered alphabetically.

2. 5-methyl-9-oxodecanoic acid is wrong because it says decanoic acid when there is an alkene present.

3. 9-oxo-5-methyldecanoic acid is wrong because it says decanoic acid when there is an alkene present, and because the substituents aren't ordered alphabetically.

4. 10-carboxy-5-methyldecan-2-one is wrong because the carboxylic acid group isn't highest priority and it omits the alkene in this compound.

When naming an organic compound by the IUPAC, it's best to first start by identifying the functional groups present.

We have an amide shown here:

We have an ethyl group shown here:

and Finally we have an alcohol (hydroxy) group shown here:

Next, we should identify what functional group has the highest priority, as that will form the base name of the compound:

According to IUPAC convention, Carboxylic Acid derivatives including Amides have the highest priority then carbonyls then alcohols, amines, alkenes, alkynes, and alkanes, so in this case the Amide group has the highest priority and therefore makes up the name of the base compound.

Next, we want to number the longest carbon chain with the highest priority functional group with the lowest number. In this case this means we want the carbonyl of the amide to be carbon number #1, so let's start there and number the carbon chain.

You should get something like this:

Now that we have numbered the carbon chain we can begin our naming.

Let's start with the base name:

According to IUPAC convention the base name for an amide compound is -amide, so in this case we have a hexanamide, which can also be written as hexan-1-amide, but this isn't needed as it as the amide is at carbon 1.

Next we have an ethyl group at carbon 4, which gives us:

4-ethylhexanamide.

Finally we have an alcohol group at carbon 5, which as a substituent is referred to as an hydroxy.

so we have a 5-hydroxy group.

Now we must order the substituents in alphabetical order to follow IUPAC rules, so our final answer is 4-ethyl-5-hydroxyhexanamide.

Now let's go over the wrong answer choices:

1. 6-carboxamide-3-ethylhexan-2-ol is wrong because it interprets the amide as being lower priority than the alcohol.

2. 4-ethyl-5-hydroxypentanamide is incorrect because the longest carbon chain is six carbons long, not 5.

3. 3-ethyl-2-hydroxyhexan-6-amide is wrong because the amide group isn't the lowest number it can possibly be, as according to IUPAC rules the highest priority functional group should have the lowest possible numbering.

4. 3-ethyl-2-hydroxypentan-5-amide is wrong because the amide isn't the lowest number it can be and the longest carbon chain is 6 carbons, not 5.

When naming an organic compound by the IUPAC, it's best to first start by identifying the functional groups present.

In this particular case we have:

An amide shown here:

A Bromine (bromo) group shown here:

A Fluorine (fluoro) group shown here:

and A chlorine (chloro) group shown here:

Next, we should identify what functional group has the highest priority, as that will form the base name of the compound:

According to IUPAC convention, Carboxylic Acid derivatives including amides have the highest priority then carbonyls then alcohols, amines, alkenes, alkynes, and alkanes, so in this case the amide group has the highest priority and therefore makes up the name of the base compound.

Next, we want to number the longest carbon chain with the highest priority functional group with the lowest number. In this case this means we want the carbon on the ring that the amide is attached to to be #1, so let's start there and number the carbon chain, and then we go in alphabetical order for the substituents, so we make bromo a lower number than chloro.

You should get something like this:

Now that we have numbered the carbon chain we can begin our naming.

Let's start with the base name:

Since this is a cyclic compound we name the compound cyclohexanecarboxamide, as in IUPAC nomenclature you name the ring normally then put carboxamide at the end to show it has an amide attached to it.

Next we number the substituent alkyl halides so that they are in alphabetically order and the one that is nearest to the beginning of the alphabet has the lowest priority, so we have a 3-bromo, 4-fluoro, and 5-chloro.

Putting this together and ordering the substituents named in alphabetical order, we get 3-bromo-5-chloro-4-fluorocyclohexanecarboxamide as our final answer.

Now let's go over the wrong answers:

1. 3-bromo-5-chloro-4-fluorocyclohexanamide is wrong because in IUPAC nomenclature we must name the ring normally and then put carboxamide after it.

2. 3-bromo-5-chloro-4-fluorohexanamide is wrong because it ignores the fact that this compound is cyclic (a ring), and would be the correct name if this were a straight chain compound.

3. 5-bromo-3-chloro-4-fluorocyclohexanecarboxamide is wrong because the substituents aren't numbered in alphabetical order so that the lowest number alkyl halide is closest to the beginning of the alphabet.

4. 5-bromo-3-chloro-4-fluorocyclohexanamide is wrong because the substituents aren't numbered in alphabetical order so that the lowest number alkyl halide is closest to the beginning of the alphabet. It is also wrong because in IUPAC nomenclature we must name the ring normally and then put carboxamide after it.

When naming an organic compound by the IUPAC, it's best to first start by identifying the functional groups present.

In this particular case we have:

An acyl chloride:

An Alcohol (hydroxy) group:

and an Ethyl group:

Next, we should identify what functional group has the highest priority, as that will form the base name of the compound:

According to IUPAC convention, Carboxylic Acid derivatives including acyl halides have the highest priority then carbonyls then alcohols, amines, alkenes, alkynes, and alkanes, so in this case the Ester group has the highest priority and therefore makes up the name of the base compound.

Next, we want to number the longest carbon chain with the highest priority functional group with the lowest number. In this case this means we want the carbon on the ring attached to the acyl chloride to be carbon number #1, so let's start there and number the carbon chain.

You should get something like this:

Let's start with the base name:

According to IUPAC convention the base name for an acyl halide ring requires us to name the ring normally and then put carbonyl ____ide (where ___ is the name of the halogen) after it. In this case the base name becomes cyclopentanecarbonyl chloride.

Next we must try to make the next greatest priority group the lowest priority, which is the alcohol (hydroxy) group, and since this is next to carbon #1 it becomes carbon #2.

This means our name thus far for the compound is 2-hydroxycyclopentanecarbonyl chloride.

Finally we have an ethyl group at carbon #4, so it becomes 4-ethyl. Now we order our substituents named in alphabetical order so the final name is 4-ethyl-2-hydroxycyclopentanecarbonyl chloride.

Now let's look at the wrong answer choices:

1. 4-ethyl-2-hydroxycyclopentonyl chloride is wrong because according to IUPAC nomenclature cyclic acyl halides must be named normally with carbonyl ___ide (where ___ is the name of the halide) at the end of the name of the ring.

2. 4-ethyl-2-hydroxypentonyl chloride is wrong because the base name used is for the straight chain version of the compound when this compound is a ring.

3. 3-ethyl-5-hydroxypentonyl chloride is name because the hydroxy group is a higher priority than the ethyl substituent, so it needs to have a lower number if possible according to IUPAC rules. It is also wrong because the base name used is for the straight chain version of the compound when this compound is a ring.

4. 3-ethyl-5-hydroxycyclopentonyl chloride is wrong because the hydroxy group is a higher priority than the ethyl substituent, so it needs to have a lower number if possible according to IUPAC rules. It is also wrong because according to IUPAC nomenclature cyclic acyl halides must be named normally with carbonyl ___ide (where ___ is the name of the halide) at the end of the name of the ring.

When naming an organic compound by the IUPAC, it's best to first start by identifying the functional groups present.

In this particular case we have:

A Carboxylic Acid:

A Ketone:

An Alcohol (hydroxy) group:

Next, we should identify what functional group has the highest priority, as that will form the base name of the compound:

According to IUPAC convention, Carboxylic Acid and their derivatives have the highest priority then carbonyls then alcohols, amines, alkenes, alkynes, and alkanes, so in this case the Carboxylic acid group has the highest priority and therefore makes up the name of the base compound.

Next, we want to number the longest carbon chain with the highest priority functional group with the lowest number. In this case this means we want the carbon on the ring attached to the carboxylic acid to be carbon number #1, so let's start there and number the carbon chain.

You should get something like this:

Now that we have numbered the carbon chain we can begin our naming.

Let's start with the base name:

According to IUPAC convention the base name for an carboxylic acid ring requires us to name the ring normally and then put carboxylic acid after it. In this case the base name becomes cyclohexanecarboxylic acid.

The next highest priority group is the ketone next to the carbon #1, which is named as a substituent as it is lower priority than the carboxylic acid, so we have 2-oxocyclohexanecarboxylic acid.

Finally we have a hydroxy group at carbon 3, which is 3-hydroxy, so after ordering the substituents alphabetically we get the final answer of 3-hydroxy-2-oxocyclohexanecarboxylic acid.

Now let’s look at the wrong answers:

1. 3-hydroxy-2-oxocyclohexanoic acid is wrong because according to IUPAC nomenclature cyclic acids must be named normally with carboxylic acid at the end of the name of the ring.

2. 3-hydroxy-2-oxohexanoic acid is wrong because this is a ring, and that is the name given to the straight chain version of this compound.

3. 5-hydroxy-6-oxocyclohexanecarboxylic acid is wrong because it ignores the fact that the ketone group is a higher priority substituent than the alcohol, so it can be assigned to be on carbon 2 instead of 6.

4. 5-hydroxy-6-oxohexanoic acid is wrong because this is a ring, and that is the name given to the straight chain version of this compound. It is also wrong it ignores the fact that the ketone group is a higher priority substituent than the alcohol, so it can be assigned to be on carbon 2 instead of 6.

When naming an organic compound by the IUPAC, it's best to first start by identifying the functional groups present.

In this particular case we have:

An acyl chloride:

An alcohol:

and An amine:

Next, we should identify what functional group has the highest priority, as that will form the base name of the compound:

According to IUPAC convention, Carboxylic Acid derivatives including acyl halides (in the case the acyl chloride) have the highest priority then carbonyls then alcohols, amines, alkenes, alkynes, and alkanes, so in this case the acyl chloride group has the highest priority and therefore makes up the name of the base compound.

Next, we want to number the longest carbon chain with the highest priority functional group with the lowest number. In this case this means we want the carbonyl carbon on the acyl chloride to be carbon number #1 as it has the highest priority, so let's start there and number the carbon chain.

You should get something like this:

Let's start with the base name:

According to IUPAC naming conventions for straight chained acyl halides their names end with -oyl __halide (where __ is the name of the halide), so in this case we have -oyl chloride. Since this is a five carbon chain we have pentanoyl chloride as our base name.

Next, notice the next highest priority group is an alcohol substituent (hydroxy) group on carbon #3, so we have 3-hydroxypentanoyl chloride.

Finally we have an amine on carbon #4, so we name this substituent 4-amino, so after ordering the substituents alphabetically we get the final answer: 4-amino-3-hydroxypentanoyl chloride.

Now let’s look at the wrong answers:

1. 4-amino-3-hydroxypentenoyl chloride is wrong because it says pentenoyl instead of pentanoyl. Pentenoyl implies there is an alkene present and there isn't.

2. 2-amino-3-hydroxypentan-5-oyl chloride is wrong because it makes the amino group a higher priority and therefore lower number than the alcohol and acyl halide, when naming must be done according to the acyl halide as it is the highest priority group.

3. 4-amino-3-hydroxyhexanoyl chloride is wrong because it miscounts the number of carbons on the longest chain, which is 5, not 6.

4. 4-amino-3-hydroxybutanoyl chloride is wrong because it miscounts the number of carbons on the longest chain, which is 5, not 4.

The longest carbon chain is carbons long (thus ""), and the double bond makes it an alkene (thus ""). The highest priority functional group is the double bond, and the carbon chain must be numbered such that this functional group is given the lowest number carbon. Counting from left to right puts the double bond between carbons and , which is lower than counting from right to left , therefore the numbering goes from left to right, and the molecule is thus a "." The substituents are a bromine on carbon and a chlorine on carbon . IUPAC rules state that the substituents are listed in alphabetical order when naming (thus "").

Finally, stereochemistry must be taken into account. On carbon , the bromine is of higher priority than the methyl group (when taking atomic number into account, per the Cahn-Ingold-Prelog rules), and is located "above" the double bond. On carbon , the chlorine group is higher priority, and is located "below" the double bond. Because the higher priority groups are across the double bond from each other, the molecule is given the "E" designation.