Chem 234 Exam 3 questions with
answers
Naming |system |for |linear |carboxylic |acids |(IUPAC) |- |correct |answers✔✔Drop |"-e" |and
|add |"-oic |acid" |
Ex. |Pentanoic |acid
Naming |system |for |carboxylic |acids |(common) |- |correct |answers✔✔Depends |on
|number |of |carbons:
1- |Formic
2 |- |acetic
3 |- |propionic
4 |- |butyric |
5 |- |Valeric
6 |- |Caproic |
Ex. |Acetic |acid
Naming |cyclic |carboxylic |acids |(IUPAC) |- |correct |answers✔✔Name |cyclic |group
|normally, |ending |with |"carboxylic |acid" |
Ex. |3-ethylcyclopentanecarboxylic |acid
Acidity |trends |in |carboxylic |acids |- |correct |answers✔✔Nearby |electron |withdrawing
|groups |increase |acidity |through |inductive |effect. |Acidity |is |used |to |isolate
|compounds |by |deprotonating |and |protonating |to |make |soluble/insoluble |in |H2O
What |reactions |can |be |carried |out |with |a |carboxylic |acid? |- |correct |answers✔✔-
|reaction |with |a |base |(NaH) |then |electrophile |to |provide |esters |
- |reduction |to |alcohols |with |LAH/H3O |or |BH3-THF/H3O
- |nucleophylic |acyl |substitution |to |convert |-OH |to |a |different |group
, Difference |between |routes |of |making |a |carboxylic |acid |an |ester? |- |correct
|answers✔✔You |can |deprotonate |the |OH |with |a |base, |then |react |with |an |electrophile
|(alkyl |halide) |
Alternatively, |you |can |go |through |Fischer |esterification, |which |involves |activating |the
|carbonyl |and |an |alcohol |attacking |the |C |at |the |carbonyl. |In |one |case |the |carboxylic
|acid |is |the |nucleophile, |in |the |other |case |it |is |the |electrophile
What |is |an |advantage |of |using |BH3-THF |and |acid |to |reduce |carboxylic |acids |to
|alcohols |over |LAH? |- |correct |answers✔✔Milder |reducing |agent, |selective |for
|carboxylic |acids |over |other |groups
What |do |you |use |to |convert |a |carboxylic |acid |to |an |acid |chloride? |What |are |the
|byproducts? |(Know |mechanism) |- |correct |answers✔✔SOCl2 |- |HCl, |SO2 |gas
Characteristics |of |Fischer |Esterification |(Know |mechanism) |- |correct |answers✔✔-
|use |small |amount |of |acid |(usually |H2SO4) |in |a |catalytic |quantity, |just |to |activate
|carbonyl |so |alcohol |can |attack
- |reaction |is |an |equilibrium |process |equally |favoring |the |products |and |reactants
- |drive |reaction |to |the |products |by |adding |an |excess |of |one |reagent |or |removing
|H2O |as |the |reaction |occurs
What |is |the |result |of |intramolecular |Fischer |Esterification? |What |denotes |the
|reaction? |- |correct |answers✔✔Formation |of |cyclic |esters |(lactones). |One |end |of |the
|molecule |has |a |carboxylic |acid, |the |other |end |has |an |alcohol
Naming |system |for |lactones |and |lactams: |- |correct |answers✔✔Use |Greek |lettering
|system, |start |lettering |from |the |alpha |position. |The |last |Greek |letter |you |use |before
|you |reach |the |ester |O |names |the |lactone/lactam |
- |lactones |are |cyclic |esters
- |lactams |are |cyclic |amides |
Ex. |Delta-lactone
answers
Naming |system |for |linear |carboxylic |acids |(IUPAC) |- |correct |answers✔✔Drop |"-e" |and
|add |"-oic |acid" |
Ex. |Pentanoic |acid
Naming |system |for |carboxylic |acids |(common) |- |correct |answers✔✔Depends |on
|number |of |carbons:
1- |Formic
2 |- |acetic
3 |- |propionic
4 |- |butyric |
5 |- |Valeric
6 |- |Caproic |
Ex. |Acetic |acid
Naming |cyclic |carboxylic |acids |(IUPAC) |- |correct |answers✔✔Name |cyclic |group
|normally, |ending |with |"carboxylic |acid" |
Ex. |3-ethylcyclopentanecarboxylic |acid
Acidity |trends |in |carboxylic |acids |- |correct |answers✔✔Nearby |electron |withdrawing
|groups |increase |acidity |through |inductive |effect. |Acidity |is |used |to |isolate
|compounds |by |deprotonating |and |protonating |to |make |soluble/insoluble |in |H2O
What |reactions |can |be |carried |out |with |a |carboxylic |acid? |- |correct |answers✔✔-
|reaction |with |a |base |(NaH) |then |electrophile |to |provide |esters |
- |reduction |to |alcohols |with |LAH/H3O |or |BH3-THF/H3O
- |nucleophylic |acyl |substitution |to |convert |-OH |to |a |different |group
, Difference |between |routes |of |making |a |carboxylic |acid |an |ester? |- |correct
|answers✔✔You |can |deprotonate |the |OH |with |a |base, |then |react |with |an |electrophile
|(alkyl |halide) |
Alternatively, |you |can |go |through |Fischer |esterification, |which |involves |activating |the
|carbonyl |and |an |alcohol |attacking |the |C |at |the |carbonyl. |In |one |case |the |carboxylic
|acid |is |the |nucleophile, |in |the |other |case |it |is |the |electrophile
What |is |an |advantage |of |using |BH3-THF |and |acid |to |reduce |carboxylic |acids |to
|alcohols |over |LAH? |- |correct |answers✔✔Milder |reducing |agent, |selective |for
|carboxylic |acids |over |other |groups
What |do |you |use |to |convert |a |carboxylic |acid |to |an |acid |chloride? |What |are |the
|byproducts? |(Know |mechanism) |- |correct |answers✔✔SOCl2 |- |HCl, |SO2 |gas
Characteristics |of |Fischer |Esterification |(Know |mechanism) |- |correct |answers✔✔-
|use |small |amount |of |acid |(usually |H2SO4) |in |a |catalytic |quantity, |just |to |activate
|carbonyl |so |alcohol |can |attack
- |reaction |is |an |equilibrium |process |equally |favoring |the |products |and |reactants
- |drive |reaction |to |the |products |by |adding |an |excess |of |one |reagent |or |removing
|H2O |as |the |reaction |occurs
What |is |the |result |of |intramolecular |Fischer |Esterification? |What |denotes |the
|reaction? |- |correct |answers✔✔Formation |of |cyclic |esters |(lactones). |One |end |of |the
|molecule |has |a |carboxylic |acid, |the |other |end |has |an |alcohol
Naming |system |for |lactones |and |lactams: |- |correct |answers✔✔Use |Greek |lettering
|system, |start |lettering |from |the |alpha |position. |The |last |Greek |letter |you |use |before
|you |reach |the |ester |O |names |the |lactone/lactam |
- |lactones |are |cyclic |esters
- |lactams |are |cyclic |amides |
Ex. |Delta-lactone
