- WELCOME TO PART THREE
OF THE VIDEO TUTORIAL SERIES FOCUSING ON THE REACTION
OF ORGANIC FUNCTIONAL GROUPS.
THIS SECTION IS GOING TO DELVE A BIT DEEPER
INTO THE OXIDATION AND REDUCTION OF ALCOHOLS AND CARBONYL GROUPS.
LET'S GET STARTED. ALL RIGHTY.
SO ALCOHOLS, RIGHT, WE CAN DO THE GENERIC SYMBOL OF ROH,
AND SO IF WE LOOK HERE,
WE KNOW THAT ALCOHOLS CAN BE CLASSIFIED AS PRIMARY,
SECONDARY, OR TERTIARY.
DEPENDING RIGHT,
ON THE CARBON THAT'S BEARING THAT ALCOHOL GROUP,
SO DEPENDING ON THE NUMBER OF R GROUPS,
BONDED TO THE CARBON THAT IS HOLDING OUR ALCOHOL GROUP.
WE CAN CLASSIFY THE ALCOHOLS.
SO, THE ALCOHOLS AS WE SAW FROM THE PREVIOUS TUTORIAL,
THEY ARE THE LEAST OXIDIZED.
IF CARBON IS BONDED TO OXYGEN AND INTO ALCOHOL
THAT WOULD BE THE LEAST OXIDIZED FORM UNDER THESE CONDITIONS.
NOW, WE'LL SEE,
WE RECOGNIZED HERE IS OUR OXIDATION SYMBOL.
NOTICE THAT THE R GROUP IS NOT GOING TO CHANGE.
AND HERE IS THE CARBON THAT WE'RE INTERESTED IN.
AND WE SEE THAT INITIALLY WITH THE ALCOHOL,
THERE'S ONLY ONE CARBON TO OXYGEN BOND.
HOWEVER, AS WE GO TO THE ALDEHYDE RIGHT?
NOW, WE SEE THAT WE HAVE TWO CARBON TO OXYGEN BONDS.
AND THEN, WE CAN CONTINUE THE OXIDATION PROCESS
ALL THE WAY TO THE CARBOXYLIC ACID.
WHERE NOW WE HAVE THREE CARBON TO OXYGEN BONDS.
SO, NOTICE THAT NOTHING HAS HAPPENING TO THE R GROUP.
I ALSO WANT TO POINT OUT ABOUT THE HYDROGEN'S.
SO, THIS HYDROGEN HERE,
THESE HYDROGEN'S, RIGHT, WE DON'T--
HOW COME I'M NOT TALKING ABOUT THOSE?
SO, THESE HYDROGEN'S HERE,
RIGHT, DO NOT CONSIDER.
SO, WHEN WE'RE TALKING ABOUT OXIDATION AND REDUCTION,
WE DON'T CONSIDER--
OH, WELL, THAT'S NOT TRUE. THIS ONE IS--
THIS ONE IS OKAY. SORRY ABOUT THAT.
THIS ONE WE CAN CONSIDER, BECAUSE IT'S BONDED TO CARBON.
IT'S THIS ONE HERE AND THIS ONE HERE.
WHY DON'T WE CONSIDER THOSE?
WE DON'T CONSIDER THOSE BECAUSE--
ARE THOSE HYDROGEN'S BONDED TO CARBON?
NO. RIGHT.
SO WE DO NOT CONSIDER FOR THIS ALCOHOL HYDROGEN
AND THE CARBOXYLIC HYDROGEN,
WE DON'T-- WE DON'T LOOK AT THOSE HYDROGEN'S BECAUSE, RIGHT,
THEY'RE BONDED TO OXYGEN. OKAY.
NOW, LET'S GO THROUGH SECONDARY ALCOHOLS, RIGHT?
SO, WITH SECONDARY ALCOHOLS,
THERE'S ONLY ONE POSSIBLE OXIDATION PRODUCT.
WE CAN GO FROM ONE CARBON OXYGEN BOND TO TWO.
AND THE REASON FOR THAT IS BECAUSE CARBON
CAN ONLY FORM FOUR BONDS.
AND THE BONDS BETWEEN CARBONS, RIGHT,
THAT'S OUR CARBON BACKBONE OR A SPINE.
WE'RE NOT GOING TO BE DISRUPTING THAT.
AND SO, THEN FINALLY IF WE LOOK AT TERTIARIES BASED OFF THAT,
WE CAN SEE THAT WE, RIGHT--
CANNOT BE OXIDIZED, RIGHT?
WE HAVE TO BE ABLE TO OXIDIZE THE CARBON,
WE HAVE TO BE ABLE TO LOSE THIS HYDROGEN'S.
SO, NOTICE AS LONG AS THERE'S A HYDROGEN BONDED TO THE CARBON,
IT CAN BE OXIDIZED.
BUT HERE, RIGHT, THERE ARE NO H'S BONDED TO THIS CARBON,
RIGHT, TO THE ALCOHOL CARBON. OKAY.
SO, THAT'S A REALLY IMPORTANT THING TO UNDERSTAND.
AND THEN, A GREAT REACTION
THAT COVERS MOST OF THESE CONCEPTS
WOULD BE THE ETHANOL METABOLISM.
AND SO, WE LOOKED AT IT BRIEFLY IN THE OTHER VIDEO,
BUT NOW, WE'LL LOOK AT IT IN TERMS OF THE SERIES HERE, RIGHT?
SO, IF WE START WITH ETHANOL, WE HAVE A PRIMARY ALCOHOL.
AND SO, IF THIS UNDERGOES A GENTLE OXIDATION,
THEN IT WILL GO TO THE ALDEHYDE.
AND SO-- OR--
AND THEN IF WE OXIDIZED THE ALDEHYDE.
IT WILL GO ALL THE WAY TO THE CARBOXYLIC ACID.
AND--
OR WE COULD GO DIRECTLY FROM THE ALCOHOL
TO THE CARBOXYLIC ACID IF WE USE A STRONG OXIDIZING AGENT.
ALL RIGHTY. AND SO--
AND THIS ALDEHYDE FORMATION IS ONE OF THE COMPOUNDS
THAT'S ASSOCIATED WITH THAT CRUMMY HANGOVER FEELING
FROM ALCOHOL CONSUMPTION.
SO, BRIEFLY TO REVIEW THEN RIGHT HERE, RIGHT,
THAT WHEN WE LOOK AT THE CARBOXYLIC ACID,
WE WOULD CONSIDER THOSE THE MOST OXIDIZED FORM. OKAY.
AND THEN REMEMBER, OXIDATION AND REDUCTION,
YOU CAN THINK OF THOSE AS COMPLEMENTS TO EACH OTHER.
SO, IF THE CARBOXYLIC ACID IS THE MOST OXIDIZED,
IT WOULD BE THE LEAST REDUCED-- OOPS,
AND LIKEWISE, IF WE CONSIDER THE ALCOHOLS,
THE LEAST OXIDIZED,
THEY WOULD BE THE MOST REDUCED.
SO, YOU WANT TO START THINKING ABOUT OXIDATION AND REDUCTION
IN THIS COMPLEMENTARY WAY THAT THE EXTREMES
WILL ALWAYS BE OPPOSITES.
AND SO NOW, WE'LL DO A QUICK REVIEW OF REDUCTION,
WHICH WILL JUST BE THE--
WE'LL JUST FLIP THIS OXIDATION AROUND.
ALL RIGHTY.
SO, WHEN YOU TALK ABOUT OXIDATION,
WE FOCUS ON THE ALCOHOL.
ALCOHOL IS BECOMING OXIDIZED,
SINCE THEY'RE THE LEAST--
SINCE THEY'RE THE MOST REDUCED.
WITH CARBONYLS, RIGHT,
WE RECOGNIZED OUR CARBONYL GROUP HERE.
AND WE'RE GOING ONLY FOCUS ON THE ALDEHYDES OR KEY TONES.
SO, IN THE REDUCTION OF--
OH, I GUESS-- OKAY.
WELL, WE'LL DO CARBOXYLIC ACIDS TOO, RIGHT?
AND THEY'RE RIGHT HERE, SO.
WE'LL ALSO LOOK AT CARBOXYLIC ACIDS
BECAUSE OF PRIMARY ALCOHOLS.
SO, BASICALLY, IF YOU UNDERSTAND OXIDATION REACTIONS,
THEN YOU REALLY UNDERSTAND REDUCTION REACTIONS ALREADY.
SO, LET'S TEST YOUR UNDERSTANDING.
SO, LOOK AT THIS DIAGRAM BASED OFF THE PREVIOUS PAGE,
CLASSIFY THE FUNCTIONAL GROUPS.
THE CARBOXYLIC ACID HAS BEEN DONE FOR YOU.
SO, THINK ABOUT THE RELATIONSHIP BETWEEN THE FUNCTIONAL GROUPS
IN TERMS OF OXIDATION AND REDUCTION.
IF YOU GET AN ALCOHOL,
LET'S GO AHEAD AND CLASSIFY IT AS PRIMARY,
SECONDARY, OR TERTIARY. RIGHT?
SO, THE CARBOCYCLIC ACID IS THE MOST OXIDIZED.
OUR SYMBOL HERE SHOWS US WE'RE DOING A REDUCTION.
SO, WE'LL--
THE R GROUP DOESN'T CHANGE.
SO, WHAT ARE WE GOING TO DO?
SO, FOR THE FIRST STEP HERE, RIGHT,
WE HAVE THREE CARBON TO OXYGEN BONDS.
SO, WE'LL REDUCE THAT TO ONLY TWO
AND IT WILL BECOME AN ALDEHYDE.
SO, WE'LL REPRESENT THE REDUCING HYDROGEN IN GREEN,
AND THEN WE COULD DO A FURTHER REDUCTION,
AND REMEMBERING THAT THE R GROUP IS NOT CHANGING,
AND FOCUSING ON THE CARBON HERE.
AND SO, NOW, WE GO FROM THREE BONDS TO TWO BONDS, TO ONE BOND.
AND THEN, WE'VE HAD TWO HYDROGEN ATOMS ADDED TO THE CARBON
THROUGH OUR REDUCING AGENT.
ALL RIGHT. SO, HERE YOU HAVE THE CLUE.
THIS ONE FILLING IN THE BLANKS SO,
HERE'S A SECOND PATHWAY-- OH,
LET'S FINISH THIS ONE THOUGH BEFORE WE JUMP ON, RIGHT?
SO, OUR CARBOXYLIC ACID REDUCED TWO AN ALDEHYDE.
AND THEN, OUR ALDEHYDE REDUCED TWO AN ALCOHOL.
AND THERE'S ONLY ONE R GROUP, BONDED TO THE ALCOHOL CARBON.
SO, IT'S A PRIMARY ALCOHOL.
ALL RIGHT.
SO, NOW THAT WE FINISHED THAT ONE,
AND WE CAN SAY RIGHT,
SO, THIS IS THE LEAST OXIDIZED.
AND THIS WAS A REDUCTION PATHWAY.
SO, AS WE FOLLOW THE REDUCTION DOWN, THEY--
THE COMPOUNDS BECAME MORE AND MORE REDUCED. OKAY.
SO, HERE'S OUR SECOND SERIES OF REACTIONS.
AND WE SEE THAT THERE ARE TWO R GROUPS BONDED TO THE CARBON--
THE ALCOHOL CARBON.
SO, WE WOULD DESCRIBE THIS IS A SECONDARY ALCOHOL.
AND HERE WE SEE REDUCING CONDITIONS.
SO, HOW--
WHAT FUNCTIONAL GROUP
CAN BE REDUCED TO PRODUCE A SECONDARY ALCOHOL?
WELL, WE KNOW THE R GROUPS ARE GOING TO REMAIN UNCHANGED,
AND SANDWICHED BETWEEN THEM IS THIS CARBON ATOM.
AND SO, IT'S GOING TO RIGHT,
A KEY TONE REDUCES TO A SECONDARY ALCOHOL.
SO, YOU CAN SEE THAT THIS CHART IS JUST THE REVERSE.
AND THEN OF COURSE,
WE HAVEN'T SHOWN THE TERTIARY ALCOHOLS,
BECAUSE TERTIARY ALCOHOLS DO NOT UNDERGO--
CANNOT UNDERGO OXIDATION OR REDUCTION.
SO, REMEMBER THAT THE GOAL
OF STUDYING ALL THESE REACTIONS IS TO GET TO BIOCHEMISTRY.
SO, WE WILL LOOK AT ANY D PLUS
AND NADH IN MUCH CLOSER DETAIL IN THE FUTURE.
BUT EVEN WITH JUST A LITTLE BIT OF INFORMATION WE HAVE SO FAR,
LET'S LOOK AT THE QUESTION
IN A BIOCHEMICAL REACTION REDUCTION OF CARBONYLS, RIGHT?
SO, THAT'S ADDING HYDROGEN ATOMS TO CARBONYL GROUPS.
SO, WOULD YOU EXPECT THAT TO BE CARRIED OUT
WITH ANY D PLUS OR NADH.
WELL, IT'S DEFINITELY GOING TO HAVE TO BE NADH, RIGHT?
BECAUSE THE REDUCING AGENT, RIGHT.
IT NEEDS, RIGHT--
THIS WILL BE OUR REDUCING AGENT,
BECAUSE IT NEEDS TO HAVE A HYDROGEN ATOM TO DONATE.
SO, THIS--
AND THIS HYDROGEN ATOM WOULD BE DONATED TO THE CARBONYL GROUP
TO REDUCE THE CARBONYL.
SO, WE WILL BE--
WE'LL BE LOOKING AT THAT MUCH MORE CLOSELY IN THE FUTURE.
BUT I THINK IT'S HELPFUL TO SHOW THE CONTEXT
OF WHERE WE'RE HEADED WITH BIOCHEMISTRY,
TO HELP YOU LINK YOUR LEARNING
TO THE ORGANIC FUNCTIONAL GROUPS,
TO THE BIOCHEMISTRY.
SO, JUST TO WRAP UP THIS SECTION THEN ON OXIDATION,
WE HEAR A LOT ABOUT ANTI-OXIDANTS
AND HOW IMPORTANT THEY ARE TO OUR HEALTH.
AND SO, OXIDATION REACTIONS ARE CRITICAL.
THAT'S HOW ONE OF THE MAIN REASON
WE PRODUCE ENERGY IN OUR BODY,
BUT NOT ALL OXIDATION REACTIONS ARE BENEFICIAL.
OXIDATION REACTIONS CAN FORM FREE RADICALS.
SO, A FREE RADICAL IS WHERE WE HAVE AN UNPAIRED ELECTRON,
VERY UNSTABLE. OKAY.
ANOTHER WAY TO DESCRIBE IT IS AS AN ODD-VALENCE ELECTRON.
SO, THAT'S TWO WAYS TO DESCRIBE THE SAME THING.
THE IMPORTANT THING TO KNOW THOUGH IS THAT RADICALS
RIGHT THERE ARE HIGHLY REACTIVE.
AND SO, THAT MEANS THEY'RE UNSTABLE,
BECAUSE THEY'RE HIGHLY REACTIVE,
AND SO THEY REACT WITH OUR BIOLOGICAL MOLECULES
IN A DESTRUCTIVE WAY, RIGHT?
SO, THEY'RE DESTRUCTIVE TO OUR BIOLOGICAL MOLECULES. OKAY.
SO, ANTI-OXIDANTS ARE SUBSTANCES
THAT CAN TRAP THIS UNPAIRED VALENCE ELECTRON.
AND BASICALLY, PUT IT ON A TIMEOUT SO,
WE CAN PREVENT THEM FROM DAMAGING OUR BIOMOLECULES.
AND SO, THERE'S PLENTY OF RESEARCH OUT THERE
THAT SHOWS THAT OXIDATION
FROM FREE RADICALS IS LINKED TO BIOLOGICAL AGING,
BECAUSE BASICALLY, THE AGING PROCESS IS THE DEGENERATION
OF OUR BIOCHEMISTRY.
SO, IT'S VERY INTERESTING TO LOOK AT WHAT THE COMMON
STRUCTURAL FEATURES OF ANTI-OXIDANTS.
AND MANY OF THEM USED THE AROMATIC BENZENE RING
TO TRAP THE RADICAL.
SO, LET'S--
WE REMEMBER BENZENE.
SO, IT'S THE SIXTH MEMBERED RING WITH ALTERNATING DOUBLE BONDS.
AND WE CAN DRAW THE BONDING ARRANGEMENT THIS WAY.
SO, THEN IT'S VERY COMMON TO SIMPLE SHOW IT AS A RING.
AND NOW, WE CAN SEE THAT THIS IS A REALLY GOOD REPRESENTATION,
BECAUSE THOSE ALTERNATING DOUBLE BONDS IN THE BENZENE RING.
THEY FORM A FORCE FIELD OF ELECTROSTATIC REPULSION
AROUND THE HYDROCARBON RING, ALL RIGHT.
SO, THIS FORCE FIELD OF ELECTRONS,
IT IS--
IT PROTECTS THE RING FROM REACTIONS.
AND THAT'S WHY BENZENE RINGS,
THAT'S WHAT CREATES THE STABILITY. OKAY.
SO, WE WILL SEE THAT MANY ANTI-OXIDANTS
WILL JUST USE VITAMIN E AS AN EXAMPLE.
NOTICE THERE'S A BENZENE RING.
AND NOT ONLY IS IT COMMON TO SEE BENZENE RINGS,
BUT ALSO, RIGHT--
WHAT FUNCTIONAL GROUP?
WHEN WE HAVE AN ALCOHOL GROUP ON A BENZENE RING,
WHAT DO WE CALL THAT, RIGHT?
WE CALL THAT ETHANOL.
AND SO, WHAT HAPPENS IS THAT THAT RADICAL
WITH ITS UNPAIRED ELECTRON IT--
THAT UNPAIRED ELECTRON CAN GET TRAPPED IN THE FORCE FIELD
OF THE DOUBLE BOND RINGS FORMING, RIGHT?
SO, THE AROMATIC RING TRAPS THE RADICAL,
TRAPS THAT LONE ELECTRON.
AND SO, IF YOU START STUDYING ABOUT ANTI-OXIDANTS,
YOU'LL OFTEN HEAR POLYPHENOLIC'S OR POLYPHENOLS.
AND SO, LIKE FRESH FRUITS AND VEGETABLES,
AND UNPROCESSED GRAINS HAVE THIS POLYPHENOLIC'S,
AND THEY'RE ANTI-OXIDANT PROPERTY
COMES FROM THE STABILITY
OF THE ELECTRON RING ABOVE AND BELOW THE PLANE.
ALL RIGHTY.
SO, THAT CONCLUDES THIS TUTORIAL
ON ORGANIC OXIDATION REDUCTION FOCUSING ON THE ALCOHOLS
IN CARBONYL GROUPS.
AND THEN, A LITTLE BIT IN THERE
TO MAKE US MORE EDUCATED CONSUMERS UNAWARE OF OUR HEALTH,
THE ROLE OF PHENOLS AND ANTI-OXIDANTS.
PLEASE TAKE SOME TIME NOW TO WORK A FEW HOMEWORK QUESTIONS
TO REINFORCE YOUR UNDERSTANDING.