FO 9: Functional Groups Memorization

Functional groups are specific arrangements of elements in a molecule. Any molecule with a given function group will likely behave in the exact same way as another molecule with the same group.

Alkane

all C–C single bonds (saturated, no double or triple bonds anywhere)

Alkene

at least one C=C double bond

Alkynes

at least one C≡C triple bond

Alkyl Halide

C4 H9 ends with either F, Cl, Br, I (Zig-Zag)

Alcohol

C3 H7 ending with OH (zig-zag)

Ether

C4 H10 oxygen in the middle (two pyramids beside it)

Thiol

C3 H7 Bonded to SH (Zig-zag)

Sulfide

C4 H10 sulfur in the middle (two pyramids beside it)

Ketone

Aldehyde

R=H or carbon chain Amine

Aromatic

Carboxylic Acid

Ester

Acyl Halide

Anhydride

Amide

Draw one structure of a molecule. The structure must contain at least 5 carbons, a carboxylic acid, and a sulfide

Build a 5+ carbon zigzag. Place –COOH at one end (C=O and –OH on the same terminal carbon). Put an S between two carbons somewhere in the chain (R–S–R). Count all carbons including the one in –COOH.

Draw one structure of a molecule. The structure must contain at least 5 carbons, an ester, and an ether

Ester = R–COO–R (C=O with O–R, no H). Ether = R–O–R (oxygen bridging two carbons, no carbonyl). Place them at different spots in the chain. The ester's oxygen and the ether's oxygen are separate.

Draw one structure of a molecule. The structure must contain at least 5 carbons, an aldehyde, and an alkene.

Aldehyde goes at the chain end (terminal C=O with H). The alkene (C=C double bond) goes somewhere in the middle of the chain. Remember: aldehyde C=O has an H, ketone C=O does not.

Draw one structure of a molecule. The structure must contain at least 5 carbons, a ketone, and an alcohol.

Ketone = C=O with R groups on BOTH sides (not at chain end). Alcohol = –OH on a carbon. Place the ketone in the interior and the –OH at one end. Make sure you have 5+ total carbons.

Draw one structure of a molecule. The structure must contain at least 6 carbons, an amide, and an alkyl halide

Amide = C=O bonded to nitrogen (–CONR2 or –CONH2). Alkyl halide = C–X (F, Cl, Br, or I on a carbon). Put the amide at one end and the halide at the other. The amide's carbonyl carbon counts toward your 6.

Draw one structure of a molecule. The structure must contain at least 5 carbons, a thiol, and an alkene

Thiol = –SH at the end of a carbon chain. Alkene = C=C double bond (two parallel lines). Place –SH on one end and the double bond in the middle. Don't confuse thiol (–SH) with sulfide (R–S–R).

Draw one structure of a molecule. The structure must contain at least 5 carbons, an amine, and a carboxylic acid

This is basically an amino acid pattern. Amine = –NH2 (or –NHR, –NR2). Carboxylic acid = –COOH. Put –NH2 on one end and –COOH on the other with carbons in between.

Draw one structure of a molecule. The structure must contain at least 5 carbons, an anhydride, and an alcohol.

Anhydride = two C=O groups bridged by one oxygen (RCO–O–COR). That uses at least 2 carbons. Add more carbons to reach 5+ total, and put –OH on one of them. Don't put the –OH on a carbonyl carbon (that would make a carboxylic acid).

Draw one structure of a molecule. The structure must contain at least 6 carbons, an acyl halide, and an ether.

Acyl halide = C=O bonded to a halogen (–COX). Ether = R–O–R. Place the acyl halide at one end, then somewhere in the chain put an oxygen bridging two carbons. Make sure the ether O is separate from the acyl halide.

Draw one structure of a molecule. The structure must contain at least 5 carbons, a sulfide, and a ketone.

Sulfide = R–S–R (sulfur bridging two carbon groups). Ketone = C=O with carbons on both sides. Place S in one part of the chain and C=O in another. Neither is at the chain end.