- WELCOME TO PART FOUR OF THE VIDEO TUTORIALS
ON ORGANIC FUNCTIONAL GROUPS.
THIS TUTORIAL IS GOING TO FOCUS ON THE COMMON NAME FOR ETHERS
AND THE NAMING OF PHENOLS
AND THEN THE IUPAC NAMING FOR ESTERS.
LET'S GET STARTED. ALL RIGHTY.
SO THE IUPAC NAME FOR ETHERS IS VERY CLUNKY.
SO FOR MY CLASSES, WE WILL JUST FOCUS ON THE COMMON NAMES.
IT'S VERY STRAIGHTFORWARD.
WE NAME THE R GROUPS
AS THOUGH THEY WERE BRANCHES OR SUBSTITUENTS, RIGHT,
USING OUR HOMOLOGOUS SERIES NAMES.
SO IN THIS CASE,
WE WOULD HAVE THE TWO ETHYL GROUPS
BECAUSE THERE ARE TWO CARBONS ON EACH BRANCH. ALL RIGHT?
AND THEN WE SIMPLY END THE NAME WITH THE WORD ETHER
TO LET EVERYBODY KNOW. ALL RIGHT?
SO FOR EXAMPLE, THIS WOULD BE DIETHYL ETHER.
THIS IS ONE OF THE MOST COMMON ETHERS
AND SO IT'S FREQUENTLY JUST SIMPLY CALLED ETHER.
SO IF YOU'RE EVER READING SOMETHING AND IT DESCRIBES ETHER
AND YOU'RE WONDERING WHICH ONE, MOST LIKELY IT'S DIETHYL ETHER.
OF COURSE--SO HERE'S OUR ETHER AGAIN. OF COURSE,
THE R GROUPS DON'T HAVE TO MATCH,
SO WE COULD HAVE A METHYL ON ONE SIDE AND THEN A ONE, TWO, THREE,
FOUR BUTYL ON THE OTHER SIDE.
AND SO THERE'S REALLY NO RULES IN COMMON NAMES,
BUT WE'LL FOLLOW THE IUPAC CONVENTION, ALPHABETICAL,
SO WE WOULD CALL THIS BUTYL METHYL ETHER.
SO THAT'S ABOUT ALL THERE IS TO NAMING ETHERS.
IT'S A GOOD PRACTICE FOR STRENGTHENING YOUR UNDERSTANDING
OF THE HOMOLOGOUS SERIES, METH, ETH, PROP, BUT, AND SO ON.
AND THEN PHENOLS, WE'LL BRIEFLY GO OVER THOSE, RIGHT?
REMEMBER THAT THE OH GROUP
IS BONDED DIRECTLY TO THE BENZENE RING.
AND SO WE'VE TALKED ABOUT THESE BEFORE,
BUT I THINK IT'S WORTH A VERY BRIEF REVIEW.
THIS WOULD BE GIVEN THE ONE POSITION,
TWO, THREE, FOUR, FIVE, SIX,
SO WE WOULD HAVE A THREE CARBON BRANCH,
SO WE WOULD DESCRIBE THIS MOLECULE AS 3-PROPYLPHENOL.
AND THEN JUST A QUICK REMINDER, RIGHT, THAT AROMATIC RINGS,
BENZENE RINGS IN PARTICULAR,
ARE THE ONLY RINGS WE CAN WRITE CONDENSED FORMULAS FOR.
SO IF WE WANTED TO WRITE THE CONDENSED FORMULA
FOR PHENOL, C6H5OH.
SO REMEMBERING THAT THIS
IS GOING TO REPRESENT THE BENZENE RING
AND THEN WE WOULD HAVE THE OH COMING OFF.
OKAY. NOW, LET'S GET TO THE MORE CHALLENGING PART
OF THIS TUTORIAL, ESTERS.
SO LET'S LOOK AT HOW WE WOULD GIVE THE IUPAC NAME
FOR CARBOXYLIC ESTERS.
THE MAIN THING TO FOCUS ON HERE IS THE CARBONYL CARBON.
THE CARBONYL CARBON IS GOING TO HELP US IDENTIFY THE ROOT
OR THE PARENT CHAIN.
SO THE CARBONYL CARBON OF THE ESTER
WILL ALWAYS BE GIVEN THE ONE POSITION
AND THEN WE WANT TO COUNT CARBONS
SO WE HAVE TO GO IN THE DIRECTION OF THE CARBONS.
ALL RIGHTY.
SO NOW WE HAVE BASICALLY A FIVE CARBON PARENT OR ROOT.
ALL RIGHT? SO THIS IS-- SO WE'LL--
THIS GETS ASSIGNED THE SUFFIX ANOATE.
SO WE WOULD DESCRIBE THIS AS--SO THIS ENTIRE PART RIGHT HERE,
WELL, THERE IS THE ANOATE PART
AND SO THIS WOULD BE PENTANOATE. ALL RIGHTY.
SO WE HAVE TO MAKE SURE THOUGH THAT WE'VE ACCOUNTED FOR
ALL OF THE ATOMS IN THE COMPOUND.
SO THIS WE CONSIDER THE R GROUP
COMING OFF OF THE SINGLY BONDED OXYGEN.
WE CONSIDER THIS A BRANCH, RIGHT, OR A SUBSTITUENT.
SO THIS GOES WHERE BRANCHES ALWAYS GO, IN THE PREFIX.
SO WE HAVE ANOTHER CARBON CHAIN AS A BRANCH
AND SO WE WOULD DESCRIBE THIS AS PROPYL PENTANOATE.
I PUT A REALLY BIG GAP THERE ON ACCIDENT. ALL RIGHTY.
SO WE SEE WHERE ALL ASPECTS OF THE COMPOUND ARE ACCOUNTED FOR
THROUGH THE IUPAC NAME.
ALL RIGHTY. ESTERS ARE VERY INTERESTING
BECAUSE A LOT OF ARTIFICIAL FLAVORS ARE ESTERS.
ESTERS SMELL VERY SWEET MOST OF THE TIME. ALL RIGHTY.
SO LET'S DRAW THE SKELETAL LINE STRUCTURE FOR ETHYL BUTANOATE.
THAT WOULD SMELL LIKE--SMELL AND TASTE LIKE PINEAPPLE.
ALL RIGHT. SO THE BUTE, RIGHT,
TELLS US WE HAVE A FOUR CARBON CHAIN,
AND WE KNOW WE PUT THE CARBONYL OFF THE FIRST CARBON,
AND THE -OATE, RIGHT,
THE OATE PART TELLS US HERE WE HAVE THE ESTER. ALL RIGHT.
SO THE BUTE GAVE US THE FOUR CARBONS,
THE ANOATE GAVE US THE ESTER, AND THEN LAST BUT NOT LEAST,
EVEN THOUGH IT COMES FIRST IN THE NAME, ETHYL.
SO THAT WOULD TELL US WE WOULD HAVE TWO CARBONS
COMING OFF OF OUR ESTER GROUP OXYGEN. OKAY.
NOW, LET'S LOOK AT--THIS IS THE STRUCTURE FOR ORANGE FLAVOR.
I'VE SHOWN THE SKELETAL STRUCTURE
IN TWO DIFFERENT ORIENTATIONS
TO HELP YOU BUILD YOUR COMFORT WITH ESTERS.
SO THESE TWO--THESE ARE THE SAME COMPOUND.
WHEN IN DOUBT, NAME A COMPOUND.
IF IT GIVES YOU THE SAME NAME, THEN THEY'RE THE SAME COMPOUND.
WHENEVER WE'RE LOOKING AT CARBONYL COMPOUNDS,
WE'RE ALWAYS GOING TO FOCUS OUR ATTENTION ON THE CARBONYL CARBON
AND THIS IS GOING TO GIVE US OUR PARENT ONE, TWO.
ALL RIGHT? SO--AND THAT'S-- AND THEN HERE,
THIS TELLS US ANOATE AS THE ESTER
AND THEN WE COUNT THIS, ONE, TWO, THREE, FOUR,
FIVE, SIX, SEVEN, EIGHT, RIGHT?
SO THERE'S OUR OCTYL GROUP. OKAY.
SO NOW WE CAN PUT ALL THE PIECES TOGETHER.
THIS WOULD BE OCTYL, AND THEN TWO CARBONS IS F,
AND THEN ANOATE TO TELL EVERYBODY IT'S AN ESTER.
THIS COMPOUND IN PARTICULAR IS VERY INTERESTING,
OR THE ETHANOATE,
BECAUSE WHENEVER WE HAVE THIS CONFIGURATION RIGHT HERE,
THIS IS THE ACETATE.
AND SO THE OTHER WAY THAT YOU WILL SEE THIS WRITTEN
IS WE STILL HAVE OUR OCTYL GROUP THAT HASN'T CHANGED,
BUT ETHANOATE IS OFTEN REPLACED.
WE COULD SAY THAT THIS IS OCTYL AND I'M JUST--
I GUESS I'LL DO IT IN RED. ACETATE. OKAY?
SO HAVING ONE METHYL GROUP
COMING OFF OF THE CARBONYL CARBON
IS A VERY COMMON SITUATION AND SO WE HAVE THE COMMON NAME ACET.
WHENEVER YOU SEE ACET,
YOU KNOW THAT THE R GROUP IS EQUAL TO A METHYL GROUP
COMING OFF RIGHT HERE. ALL RIGHT?
SO BASICALLY,
WE'RE IGNORING THE CARBON OF THE CARBONYL CARBON. ALL RIGHT?
SO THERE ARE TWO NAMES.
YOU'LL EITHER SEE THIS WRITTEN AS OCTYL ETHANOATE.
MORE LIKELY, YOU'LL SEE IT WRITTEN AS OCTYL ACETATE.
SO ESTERS ARE VERY IMPORTANT.
WHEN WE GET TO THE CHAPTER WHERE WE STUDY FATS AND OILS,
FATS AND OILS ARE CALLED TRIGLYCERIDES. WHY?
BECAUSE THERE ARE THREE ESTER GROUPS PRESENT.
SO GO AHEAD AND LOOK AT THIS STRUCTURE FOR TRIGLYCERIDE
AND CIRCLE THE ESTER GROUPS. RIGHT?
WE CAN SEE THEM RIGHT HERE, ONE, TWO, THREE. OKAY.
SO THAT CONCLUDES OUR VIDEO TUTORIAL
ON NAMING ETHERS, PHENOLS, AND ESTERS.
TAKE SOME TIME NOW TO WORK A FEW HOMEWORK PROBLEMS
TO REINFORCE YOUR UNDERSTANDING.