Term
| on the MCAT, there are two things that you should think when you see a carbonyl group, what are they |
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Definition
planar stereochemistry- therefore making it suceptible to upper and lower chemical attack
and
oxygen is slightly negative, carbon slighty positive |
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Term
| lets consider the electrochemistry of a carbonyl, since carbon is slightly positive and oxygen is slightly negative, what can we look for |
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Definition
carbon will most likely be subject to a nucelophilic attack
whereas, oxygen is easily protonated |
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Term
| why do alcohols have greater boiling points that aldehydes and ketones |
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Definition
because alcohols can hydrogen bond between each other, while aldehydes and ketones can not
aldehydes and ketones can however hydrogen bond to water |
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Term
| what is a dicarbonyl and how does its alpha carbon compare to the acidity of alcohols and water |
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Definition
| a dicarbonyl's beta carbon is also a carbonyl group, this increases the acidity of the molecule much greater than alcohol and water |
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Term
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Definition
this involves a proton shift from the alpha carbon to the oxygen of the carbonyl group
the ketone or aldehyde is more often favored, but these two formations are in equilibrium at room temperature |
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Term
| what happens when an alcohol is mixed with either an aldehyde or ketone |
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Definition
a hemiacetal or hemiketal is formed
the alcohol acts as a nucelophile |
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Term
| explain when you would use a acetal or a ketal |
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Definition
| if I wanted to attach a base but didnt want it to touch the carbonyl group, I would feed the carbonyl a di-alcohol to form a blocking group, attach the base, then hydration to bring blocking group back to a carbonyl |
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Term
| in aldol condesation reactions, once the alpha hydrogen has been removed, what acts as a nucelophile |
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Definition
| the enol acts as a nucleophile to attack the carbonyl on the other molecule to form an alkoxide ion |
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Term
| how does the haloform reaction go from a ketone to a carboxylic acid |
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Definition
| when a methyl ketone is reacted with a halogen and a base, it will produce a trihalo product (the alpha carbon will completely halogenated), then the base will nucleophilically attack the carbon on the carbonyl which reduces the oxygen, then the reduced oxygen kicks off the trihalo alpha carbon |
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Term
| what does a Wittig reaction |
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Definition
| this converts a ketone to an alkene |
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Term
| according to IUPAC rules, what functional group takes priority over everything else |
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Definition
| the carbonyl carbon of a carboxylic group |
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Term
| when you see a carboxylic acid, what should you think in terms of reaction mechanisms |
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Definition
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Term
| what is more acidic: a carboxylic acid or a carboxylic acid with a electron withdrawing group on its alpha carbon |
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Definition
| a carboxylic acid with an electron withdrawing group on its alpha carbon |
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Term
| describe how the structure on the carboxylic acid gives it a higher boiling point, a lower melting point and makes it soluble in non polar sovlents |
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Definition
carboxylic acids can form dimers, which are very strong double hydrogen bonds, this increases the boiling point by increasing the molecular weight leaving the liquid phase
because of the structure, carboxylic acids impede the crystal lattice phase and have a lower melting point
because carboxylic acids form dimers, they can be soluble in non polar solvents because it will not affect the double hydrogen bonding |
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Term
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Definition
| this is when carboxylic acid loses CO2 |
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Term
| all carboxyllic acid derivatives hydrolyze to give what |
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Definition
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Term
| what happens when an alcohol is mixed with a carboxylic acid |
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Definition
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Term
| what is transesterfication |
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Definition
| transesterfication is simply the swapping of one alkoxy group for another |
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Term
| nitrogen can take on three or four bonds, so when you seen a amine with three bonds you should do what |
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Definition
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Term
| what are three important considerations to keep in mind when dealing with amines |
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Definition
the lone pairs can act as a lewis base and donate their electrons
the lone pairs can act as a nuclephile and attack a positive charge
the lone pairs can take on a fourth bond and become partially positive charged |
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Term
| can ammonia and amines hydrogen bond |
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Definition
| yes they can and this increases their boiling point and their solublity in water |
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Term
| what happens when an amine is reacted with a ketone and aldehyde |
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Definition
| an enamine is formed when a secondary amine is used, and a imine is formed when a primary amine is used |
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Term
| what happens if a tertiary amine is feed too much acid |
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Definition
| it will protonate and form a quaternary amine, and become a poor nuclephile |
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Term
| what does the wolff-kishner reduction do |
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Definition
| it reduces a ketone or aldehyde to two hydrogens |
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Term
| amines undergo alkylation through which mechanism |
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Definition
| nucleophilic substitution |
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Term
| if you had a primary amide and you wanted to deprotonate it, what would you do |
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Definition
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