- WELCOME TO PART ONE OF A VIDEO TUTORIAL SERIES
ON ORGANIC FUNCTIONAL GROUP REACTIONS.
THIS TUTORIAL WILL FOCUS ON INTRODUCING THE REACTIONS
THAT WILL BE COVERED IN THE SERIES
AND A BRIEF REVIEW OF ACID-BASE CHEMISTRY.
LET'S GET STARTED.
SO IT'S REALLY IMPORTANT TO NOTE THAT EACH FUNCTIONAL GROUP
HAS UNIQUE CHEMICAL REACTIVITY.
AND SO, THIS SECTION IS GOING TO SET US UP FOR BIOCHEMISTRY.
BIOLOGICAL MOLECULES CAN BE VERY LARGE.
SO WE HAVE TO REMEMBER TO FOCUS ON THE FUNCTIONAL GROUP.
THE BULK OF THE MOLECULE WILL SIMPLY SYMBOLIZE AS R
FOR REST OF THE MOLECULE.
AND WE WILL BE FOCUSING ON A VERY SMALL ASPECT
OF THE MOLECULE, BUT THAT'S WHERE THE CHEMICAL CHANGE
IS OCCURRING.
SO MOST REACTIONS ONLY AFFECT ONE FUNCTIONAL GROUP
AT A TIME.
SO RECOGNIZING THE FUNCTIONAL GROUPS AND LOOKING FOR CHANGES
IS A REALLY GREAT STRATEGY TO HELP MAKE SENSE OUT OF THIS.
SO LET'S PRACTICE THAT SKILL FIRST.
LOOK AT OUR REACTANT AND PRODUCT.
AND THEN GO AHEAD AND CIRCLE THE CHANGE
THAT YOU SEE OCCURRING.
SO NOTICE WE HAVE TWO FUNCTIONAL GROUPS, RIGHT?
BUT THE CARBOXYLIC ACID REMAINS THE SAME.
WE CAN SEE THAT THE KETONE IS CHANGING INTO AN ALCOHOL.
SO THAT'S WHERE WE WOULD FOCUS OUR ATTENTION THEN ON--
AND THIS IS WHAT WE'RE GOING TO LEARN,
WHAT TYPE OF CHANGE THAT IS.
SO WE'LL GET TO THAT. BUT RIGHT NOW,
WE'RE JUST TRAINING OUR EYE TO LOOK FOR CHANGES.
NOW, IT'S IMPORTANT TO CONNECT ALL OF THESE TO WHAT
WE'VE BEEN LEARNING ABOUT REACTIONS.
AND SO, ALL BIOCHEMICAL REACTIONS ARE PRETTY MUCH
CATALYZED BY ENZYMES, ESPECIALLY THE ONES INVOLVED
IN FUNCTIONAL GROUP CHANGES.
SO FUNCTIONAL GROUP REACTIVITY.
SO CATALYSTS, LET'S REMEMBER WHAT ARE CATALYSTS.
THEY'RE A SUBSTANCE THAT DECREASES THE ACTIVATION ENERGY
TO INCREASE THE REACTION RATE.
AND THE INTERESTING THING ABOUT A CATALYST
IS THAT IT IS NOT CONSUMED IN THE REACTION.
SO THE GREAT THING ABOUT A CATALYST
IS THAT WE ONLY NEED A SMALL AMOUNT, AND IT CAN BE REUSED
OVER AND OVER.
IT CATALYZES REACTION, AND THEN IT'S READY FOR THE NEXT SET
OF REACTANTS.
ENZYMES ARE ESPECIALLY IMPORTANT IN OUR BODIES.
IF WE'RE IN THE LAB, WE CAN BOIL IT
OR PUT SOME STRONG ACID OR BASE
OR SOME KIND OF HEAVY TOXIC METAL.
AND IN THE REACTION FLASK, IT'S FINE.
BUT INSIDE OUR BODIES, RIGHT? WE NEED TO BE GENTLE.
WE WANT TO HAVE OUR PH AT APPROXIMATELY 7.4.
WE WANT TO BE AT BODY TEMPERATURE, RIGHT?
THAT SORT OF THING, RIGHT?
TO KEEP OURSELVES ALIVE.
SO WE CAN'T USE EXTREME REACTION CONDITIONS.
WE NEED TO BENEFIT FROM THE CATALYSTS
WHICH ARE ENZYMES.
SO LET'S KIND OF DO A BRIEF RECAP
OF WHAT WE KNOW ABOUT REACTIONS AND HOW WE DESCRIBE THEM
USING A DIAGRAM.
SO WE'LL DO A ONE-STEP EXOTHERMIC.
SO AS SOON AS YOU HEAR THE WORD EXOTHERMIC
YOU THINK NEGATIVE X, HEAT AS A PRODUCT.
AND THEN IN THIS CASE, WE'RE GOING FOR A LARGE
ACTIVATION ENERGY, SO THAT'S A LARGE E SUB A.
AND SO IF WE WRITE OUR DIAGRAM, MAKE SURE I CAN FIT IT
ON THE SPACE. OKAY. SO OF COURSE IT'S RIGHT,
IT'S TIME ON THE X, ENERGY ON THE Y.
SO THIS REACTION, RIGHT?
LARGE ACTIVATION ENERGY, PRODUCTS ARE MORE STABLE
THAN REACTANTS.
SO THERE'S OUR REACTANTS AND OUR PRODUCTS.
AND SO THIS EXOTHERMIC PART IS HERE.
AND THEN THE LARGE ACTIVATION ENERGY IS HERE, RIGHT?
AND THE TOP OF THE CURVE HERE IS OUR TRANSITION STATE.
OKAY. SO NOW, LET'S OVERLAY A SECOND CURVE,
WE'LL USE A DASH LINE FOR THE CATALYST.
SO WITH THE ENZYMES OR THE CATALYST DO,
WE REMEMBER IS THEY LOWER THAT ACTIVATION ENERGY.
SO NOW WE HAVE A MUCH SMALLER ACTIVATION ENERGY.
AND SO THIS REACTION CAN HAPPEN MUCH FASTER BECAUSE
WE HAVE A MUCH SMALLER HILL TO CLIMB.
IF YOU HAVE TO RUN TO THE TOP OF THIS HILL,
YOU COULD DO IT MUCH FASTER THAN YOU COULD RUN TO THE TOP
OF THIS BIG HILL.
ALL RIGHTY.
SO WE WANT TO BE KEEPING ALL OF THESE CONCEPTS IN MIND
AS WE THINK ABOUT THE REACTION.
SO WE'LL GO TO THE NEXT PAGE AND LET'S DO A BRIEF REVIEW
OF ACID-BASE REACTIONS.
BECAUSE THESE ARE THE MOST FREQUENT AND FUNDAMENTAL.
SO THEY ARE ALWAYS OCCURRING IN THE BACKGROUND.
SO LET'S FOCUS ON SOME ACID-BASE CHEMISTRY.
SO HERE WE HAVE AN EXAMPLE OF PYRUVIC ACID.
AND THIS IS A COMPOUND THAT WE'LL SEE WHEN WE LEARN
ABOUT GLYCOLYSIS AND OTHER BIOCHEMICAL REACTIONS.
AND WE RECOGNIZE THAT IT'S THE ACID.
AND THEN OF COURSE WE ALWAYS SEE SODIUM HYDROXIDE AS A BASE.
AND SO WE KNOW THAT THE ACID IS THE PROTON DONOR.
SO THE PYRUVIC ACID WILL DONATE ITS PROTON, RIGHT?
AND SO NOTICING THAT THE REACTION IS ONLY HAPPENING
AT ONE FUNCTIONAL GROUP, SO IT'LL GIVE ITS PROTON
TO THE HYDROXIDE TO FORM WATER, AND THEN WE HAVE THIS SODIUM,
IT'S BASICALLY A SPECTATOR ION.
AND SO IT'LL BE FLOATING AROUND AS A COUNTER ION
TO OUR PYRUVATE.
AND IF WE LOOK AT THIS COMPLEX HERE, RIGHT?
WE WOULD DESCRIBE THIS AS A CARBOXYLATE SALT.
OKAY. NOW, LET'S LOOK AT ANOTHER REACTION.
SO HERE WE LOOK IN THERE'S TWO PHENOLS AND ALCOHOL AND AMINE.
AND WE LOOK AND WE SEE AN ACID.
SO WE RECOGNIZE AMINES AS WEAK, THIS IS THE WEAK BASE PART.
WE HAVE A WEAK BASE, AND YOU'VE MEMORIZED YOUR STRONG ACIDS
SO YOU LOOK HERE AT HYDROCHLORIC ACID
AND YOU RECOGNIZE IT AS ACID.
SO THE BASE IS THE PROTON ACCEPTOR, RIGHT?
HYDROCHLORIC ACID WILL PROTONATE THE AMINE.
SO NOTICE THAT THE BULK OF THE MOLECULE,
NOTHING'S CHANGING.
WE COULD BASICALLY THINK OF THIS AS A GIANT R GROUP.
AND THAT'S WHERE WE'RE HEADED, ALL RIGHT?
SO WE HAVE THE METHYL GROUP COMING OFF
AND THEN WE WOULD HAVE H2+ AND THE CHLORIDE.
AND SO WE WOULD HAVE CREATED AN AMMONIUM SALT.
SO THEN REMEMBER THE IMPORTANCE OF THE IONIZED FORM
OF THE CARBOXYLATE AND THE AMMONIUM SALT.
THAT CREATES WATER SOLUBILITY.
SO IF WE LOOK AT THIS NEXT SET OF EXERCISES,
IT'S A GOOD OPPORTUNITY TO PRACTICE CLASSIFYING
YOUR FUNCTIONAL GROUPS AND THEN PREDICTING WATER SOLUBILITY
OF THE REACTANTS AND THE PRODUCTS BELOW.
SO WE CAN SEE HERE THAT THIS LARGE HYDROCARBON GROUP,
WE DESCRIBE THAT AS A FATTY GROUP,
IT'S HYDROPHOBIC.
AND THEN WE HAVE OUR CARBOXYLIC ACID GROUP,
SO WE WOULD CLASSIFY THIS IS A FATTY ACID.
AND THEN THERE'S OUR HYDROXIDE.
HERE, WE HAVE THE CARBOXYLATE SALT.
SO THE FATTY ACID IS NOT WATER SOLUBLE.
THIS LARGE HYDROCARBON REGION REPELS THE WATER.
SO EVEN THOUGH WE HAVE A POLAR GROUP HERE
THAT'S WEAKLY ACIDIC, IT'S NOT STRONG ENOUGH TO OFFSET
ALL OF THESE NONPOLAR HYDROCARBONS.
HOWEVER, AS SOON AS WE HAVE A FULL CHARGE NOW,
THE CARBOXYLATE SALT IS WATER SOLUBLE.
AND ANOTHER NAME FOR THIS CARBOXYLATE SALT IS SOAP.
AND THEN WE'LL PRACTICE THE OTHER WAY,
SO HERE WE HAVE OUR AMINE. AND WE COULD BE MORE SPECIFIC
WHAT TYPE OF AMINE IS THIS.
WE ONLY SEE THERE ARE TWO 'R' GROUPS COMING OFF
OF THE NITROGEN.
SO THE MOST ACCURATE WOULD BE A SECONDARY AMINE.
AND THIS ONE, THERE IS SOME H BONDING HERE,
BUT THERE'S ALSO QUITE A FEW NONPOLAR GROUPS.
SO THIS ONE, WE WOULD EXPECT TO HAVE VERY LOW WATER SOLUBILITY
BECAUSE IT'S RIGHT AT THE CUSP OF THAT RATIO, RIGHT?
WE KNOW THAT THE POLAR GROUPS CAN SOLUBILIZE..
UP TO FOUR TO SIX NONPOLAR CARBONS.
SO THIS ONE'S RIGHT ON THE CUSP.
SO THERE MIGHT BE A LITTLE BIT OF WATER SOLUBILITY
BUT VERY LOW, NOT ENOUGH TO REALLY BE USEFUL
IF YOU WANT TO HAVE THIS IN AN AQUEOUS SOLUTION.
SO WE TAKE OUR WEAK BASE,
WE REACT IT WITH THE STRONG ACID,
AND WE PRODUCE THE AMMONIUM SALT AGAIN.
AND THEN THAT'S THE POWER OF CHARGE, RIGHT?
WITH THAT FULL CHARGE, THEN WATER SOLUBLE.
SO ACID-BASE REACTIONS ARE ALWAYS POSSIBLE.
SO WE WANT IT--THEY'RE GOING TO BE LIKE A VEIL
THAT'S LAYERED ABOVE BEFORE AND AFTER ANY REACTION
THAT WE PERFORM.
SO WE ALWAYS WANT TO KEEP ACID-BASE CHEMISTRY
IN OUR AWARENESS.
SO LET'S LOOK A LITTLE MORE AT THE ENERGETIC THOUGH
AND TIE THIS TO WHAT WE TALKED ABOUT WITH ENZYMES
AND CATALYSTS AND THINGS.
THE BIOCHEMICAL REACTIONS WHERE THE FUNCTIONAL GROUP CHANGES,
THEY HAVE THE LARGE ACTIVATION ENERGIES.
BUT WE HAVE TO COMPARE THOSE TO ACID-BASE REACTIONS
WHICH HAVE A VERY LOW ACTIVATION ENERGY, SMALL, ALL RIGHT?
SO IF WE'RE LOOKING AT THE ACID-BASE REACTION
AND WE'RE DOING A REACTION ENERGY DIAGRAM,
SO IF WE JUST SIMPLY THINK ABOUT FOR EXAMPLE,
THIS IS SIMPLE DEPROTEINIZATION, WE'LL JUST REPRESENT THIS
AS ANY WEAK ACID.
WHEN WE GO TO DO THE REACTION ENERGY DIAGRAM,
IT ALMOST LOOKS FLAT, RIGHT?
WE HAVE A VERY SMALL E SUB A.
IT'S SO SMALL I CAN'T EVEN REALLY DRAW IT IN.
SO IF YOU'RE EVER FRUSTRATED AND SAYING,
"I WISH THERE WAS A PROTON THERE."
OR, "I WISH THAT PROTON WOULD GO AWAY."
YOU CAN ALWAYS USE WHICHEVER FORM MAKES THE MOST SENSE
TO HELP YOU UNDERSTAND AND PREDICT THE REACTION.
WHEN WE'RE DOING OUR BIOCHEMICAL REACTIONS THOUGH,
AT THE VERY END, WE NEED TO REMEMBER THAT PHYSIOLOGICAL PH,
IS 7.4.
SO WHEN WE'RE ALL DONE, WE WILL SHOW ALL OF OUR
BIOCHEMICAL PRODUCTS AT PH 7.4.
SO NOW LET'S LOOK A LITTLE MORE CLOSELY
AT THE IMPLICATIONS OF THAT LARGE ACTIVATION ENERGY, RIGHT?
SO WE KNOW WITH A SMALL E SUB A, IT'S A FAST REACTION, RIGHT?
BUT WITH A LARGE E SUB A, IT'S A SLOW REACTION.
SO IF WE LOOK AT OUR REACTION ENERGY DIAGRAM, RIGHT?
NOW, WE'RE GOING TO HAVE A LARGE ACTIVATION ENERGY.
SO IF WE JUST HAVE TWO COMPOUNDS COMING TOGETHER
TO MAKE A PRODUCT, THIS IS GOING TO BE VERY SLOW.
SO THAT'S WHY WE NEED THE CATALYST.
SO THE REACTIONS THAT WE'RE LEARNING NOW,
WHEN WE GET TO THE PROTEIN CHAPTER,
WE WILL LEARN ABOUT WITH THE CATALYST,
WHICH WE'RE LEARNING IN BIOCHEMISTRY,
WOULD BE THE ENZYME, RIGHT?
WE LOWER THE ACTIVATION ENERGY AND INCREASE THE REACTION RATE.
SO THAT'S WHY ENZYMES ARE SO IMPORTANT TO OUR HEALTH.
AS WE TRANSITION TO BIOCHEMICAL REACTIONS,
LET'S KEEP FOCUSED ON OUR TARGET.
SO OUR TARGET IS TO UNDERSTAND METABOLISM.
SO UNDERSTAND THAT METABOLISM IS A COMBINATION OF CATABOLISM
AND ANABOLISM.
AND TO KEEP THESE STRAIGHT, CATABOLISM IS THE BREAKING DOWN
OF MOLECULES.
AND ANABOLISM IS THE BUILDING.
AND SO WHEN I WAS LIKE FIRST LEARNING THIS,
I ALWAYS HEAR ABOUT THE ATHLETES,
THEY USE ANABOLIC STEROIDS, RIGHT?
THEY USE THE ANABOLIC STEROIDS BECAUSE THEY'RE TRYING
TO BUILD THEIR MUSCLES.
SO CATABOLISM IS ABOUT THE BREAKING DOWN.
SO AS WE LOOK, AS WE LEARN THESE FUNCTIONAL GROUP REACTIONS,
KEEP IN MIND OUR END GAME IS TO GET TO UNDERSTANDING
CATABOLISM AND ANABOLISM.
SO WHEN WE THINK ABOUT FOOD, WE THINK ABOUT LARGE MOLECULES.
AND THEN CATABOLISM IS GOING TO BREAK THEM DOWN.
THESE WILL BE OF SOME WASTE LIKE WE EXHALE CO2
AND RELEASE WATER.
AND THEN WE GET TWO VERY IMPORTANT THINGS.
WE GET ENERGY AND WE GET SOME SMALL MOLECULES.
SO WE TAKE THE LARGE MOLECULES FROM OUR FOOD
AND WE BREAK THEM DOWN.
AND THEN WE WILL REBUILD THEM ANABOLICALLY
INTO THE LARGE BIOMOLECULES THAT WE NEED TO SUPPORT OUR HEALTH.
THERE ARE MANY IMPORTANT BIOCHEMICAL REACTIONS.
AND THE FOUR THAT WE'RE GOING TO STUDY IN THIS CHAPTER
IN PARTICULAR ARE OXIDATION AND REDUCTION,
AND BECAUSE THESE ALWAYS OCCUR TOGETHER,
WE CAN SIMPLIFY THE NAME TO REDOX,
A LITTLE EASIER TO SAY THAN OXIDATION AND REDUCTION.
AND THEN WE WILL FOCUS, OUR WATER-BASED,
WE HAVE A LOT OF BAGS OF SALTWATER WALKING AROUND.
AND SO WE WILL LOOK AT HYDRATION,
WHICH WILL BE THE GAIN OF WATER.
AND DEHYDRATION, THE LOSS OF WATER.
AND WE WILL SEE HERE THAT IT FOCUSES ON--
THIS REACTION WILL FOCUS ON FUNCTIONAL GROUP CHANGES
PRIMARILY,
MOSTLY WITH THE CARBON-CARBON DOUBLE BOND.
AND THEN WE WILL LOOK AT THE ACYL GROUP
TRANSFER REACTION.
HERE'S AN ACYL GROUP, WE'LL TALK MORE ABOUT THAT
WHEN WE GET THERE. AND THE MAIN THING--
OR MAYBE LIKE USE A QUESTION MARK, RIGHT?
SO THE ACYL GROUP IS THIS PART RIGHT HERE.
SO THE ACYL GROUP IS THIS PART.
AND THE REASON WHY WE CALLED TRANSFER
IS THIS QUESTION MARK HERE, IS THIS WE CAN VARY, RIGHT?
WE CAN CHANGE.
WE CAN CHANGE WHAT THE ACYL GROUP IS BONDED TO.
SO WE'LL EXPLORE THAT REACTION.
AND THEN THE LAST REALLY IMPORTANT REACTION
THAT WE'RE GOING TO LEARN ABOUT IN THE SERIES
IS THE PHOSPHORYL GROUP TRANSFER.
SO SIMILAR TO THE ACYL GROUP BUT THE PHOSPHORYL GROUP.
AND SO OF COURSE, THAT'S GOING TO HAVE THE PHOSPHATE IN IT
AND WE CAN GO HERE.
SO THERE'S PHOSPHATE WHERE WE COULD PUT R THERE,
PHOSPHORYL GROUP.
THESE WILL BE THE FOUR REACTIONS THAT WE ARE GOING TO LEARN ABOUT
AND STUDY IN THE FOLLOWING VIDEO TUTORIALS.
SO THIS WOULD BE A GOOD TIME TO TAKE A FEW MINUTES
TO WORK THROUGH SOME INTRODUCTORY HOMEWORK PROBLEMS
TO REINFORCE YOUR UNDERSTANDING.