Carbonyl Compounds

The carbonyl carbon will be the electrophilic molecule. The double bond of the acid will have to break and the electrons will shift toward the the oxygen. Think about the resonance structures of the molecule. Like a diens-alder reaction there will be charged poles. The positivley charged pole will be the electrophilic molecule which will be the carbonyl carbon. The nucleophile will then attatch to the electrophilic carbon forming the tetrahedral intermediate. If the nucleophile is weak, the oxygen is often protonated which makes the carbon more electrophilic driving the reaction.

Once the double bond is broken the carbon becomes an sp3 hybridized as opposed to the sp2 that is was previously. The shape becomes a tetrahedral intermediate.

In the elimination step you want the leaving group to leave the molecule. Some leaving groups such as chlorine and anhydrides are better because they are stable on thier own. Look at the molecule and see if they would be good electron sharers. Like chlorine it is very polar and doesnt want to share its electrons it makes a good leaving group because it will be fine on its own. Nitrogen and amine groups are not good leaving groups. Nitrogen is a good electron donater and often amines have good resonance stabilization. Nitrogen often times is protonated to become positivley charged and then becomes a good leaving group.

1. The double bond of the carboxylic acid is attracted to the H+. The nucleophile is weak. The oxygen attatched to the carbonyl carbon is then protonated, making the carbon much more electrophilic. The lone pairs on the nucleophile oxygen are then attracted to the electrophilic carbon. The protons are then shuffled: base comes and deprotonates the ester oxygen the electrons are donated to that oxygen making it nuetral and no longer positive. HBase also comes and takes of the alcohol group leaving with an ester with the positive charged carbonyl carbon. The hydrogen is the shuttled downward to reform the double bond. Since each of the products are used to the ending result the reaction will stay at equilibrium until the water is removed or an excess of alcohol is added.

The oxygen is protonated and the oxygen from the water molecule is attracted to the electrophilic carbon. A base comes in and deprotonates the water molecule making an alcohol. HCl is added making the H+ attracted to the lone pair on the nitrogent. The makes a positive nitrogen and a better leaving group. The group leaves and the base deprotonates the hydrogen on the oxygen at the top and the electron shuttle downward creating the pi bond.

Turning an ester into a carboxylic acid. In the first step NaOH is added. In a second step HCl is added but these cannot be added together because they would react with eachother. The electrophilic carbon is attracted to the -OH. The electrons flow up to the oxgen and the OH group is attatched to the carbonyl carbon. The leaving group then leaves and the electron flow back downward recreating the double bond. Since a strong nucleophile is then floating in the solution it will deprotonate the alcohol leaving the oxygen with a negative charge. HCl will then be added to the solution and hydronium ions will protonate the oxyget and recreate the alcohol group. Then everyone is happy and there are no charges : )

esters that have resonance and inductive effects are the most reactive.

Thermodynamic are shown in the projection because the energy between the products and the reactants are the same. Therefore there is no free energy and the system is at equilibrium. This is a state function doesnt madder how you get there, unlike a path function that represents kinetics which does madder. Activation energy is the energy need to first drive the reaction with is often H+ protons. Reactions can be exergonic, endergonic or at equilibrium.

most reactive = best leaving groupleast reactive = poor leaving groupdecreasing reactivity:chlorineanhydrideesteramine