00:00:00
quite often chemists need to use
00:00:01
solvents for all sorts of purposes but
00:00:03
not only do chemists use solvents
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solvents are used in all sorts of
00:00:07
Industries and even at home but when you
00:00:09
work with solvents in a chemistry lab
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you gradually develop grudges against
00:00:13
specific ones and in some cases they're
00:00:15
so extreme I would call them outright
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hatred the solvents I'll be discussing
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in this video are solvents that I hate
00:00:22
working with and if you've ever worked
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with some of these solvents I'm sure
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you'll hate them as well first we have
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water water's a pretty bad solvent in
00:00:29
organic chemistry and even though
00:00:31
sometimes that can be helpful for
00:00:33
removing salts and byproducts from
00:00:34
reactions it's often undesired water
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also has a relatively high boiling point
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of 100 and it has the tendency to react
00:00:41
with a lot of chemicals that you'd
00:00:42
commonly work within the lab as such
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water is a terrible solvent to work with
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but it can be helpful for doing some
00:00:48
washes if I had a choice of doing a
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reaction in water the only reason I
00:00:52
would want to do it in water is because
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it's a Greener alternative to some of
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the solvents that we use so for that
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reason I don't have a strong grudge
00:00:59
against water but it is pretty annoying
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so we'll put it into sea tier which is
00:01:03
appropriate because there's a lot of
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water in the sea now while water was the
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only solvent on here with no carbon in
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it our next compound has but a single
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carbon carbon disulfide carbon disulfide
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is extremely volatile and highly toxic
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and it usually smells pretty bad another
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downside of carbon disulfide is it
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easily oxidizes in air so it usually
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needs to be stored under an inert
00:01:24
atmosphere carbon disulfide is highly
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toxic especially with chronic exposure
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it can cause neurotoxic effects liver
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and kidney damage and is harmful if
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inhaled or absorbed through the skin
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it's definitely not something you want
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to be working with on a massive scale
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because one small spill could result in
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a lot of exposure despite that I've
00:01:42
worked with carbon disulfide quite a lot
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but it's always annoying to work with
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overall if I had to choose to do a
00:01:48
reaction in any of these solvents carbon
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disulfide would not be my first choice
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carbon disulfide would probably be like
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my last choice or second last choice so
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for that reason I'm going to put it into
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a tier because neurotoxicity liver
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toxicity and kidney toxicity that's a
00:02:02
lot of toxicity and I've worked with
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enough carbon disulfide in my life next
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we have dimethyl formamide this is a
00:02:08
relatively common solvent in organic
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chemistry but it's important to note
00:02:12
that it can explode if mixed with sodium
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hydride there's quite a few reactions
00:02:16
that use sodium hydride in dimethyl
00:02:18
formamide and that's because it's a
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polar solvent which is very good at
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dissolving polar compounds such as
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sodium hydde however sodium hydrides
00:02:26
able to react with solvents such as DMF
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and DMSO forming potentially explosive
00:02:30
mixtures if that wasn't bad enough
00:02:33
dimethyl formite is also a group 2A
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carcinogen which means it's likely to
00:02:37
cause cancer in humans it also can cause
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liver damage and is a suspected patogen
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in addition it's readily absorbed
00:02:44
through the skin making it particularly
00:02:46
hazardous DMF also has a strong
00:02:48
unpleasant smell which is pretty fishy
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it also has the tendency to dissolve
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labels off of your anmr tubes in flasks
00:02:54
which is really annoying if you suddenly
00:02:56
lose the label on your NMR tube thanks
00:02:58
DMF if you ever trying to purify
00:03:00
something like you had a reaction you
00:03:02
were running in DMF and you needed to
00:03:04
remove the solvent you might do
00:03:05
something called column chromatography
00:03:07
but if you do this with a really polar
00:03:08
solvent system like methanol D
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chloromethane you'll end up eluding some
00:03:12
of the DMF if you have a really polar
00:03:14
compound that you're trying to purify
00:03:15
effective separation can remove DMF but
00:03:17
it's pretty annoying because it's not
00:03:19
that volatile and it's dangerous around
00:03:21
acids and bases furthermore it's
00:03:24
hygroscopic and it's hard to wash out
00:03:26
but you can use lithium chloride
00:03:27
saturated water to help overall I really
00:03:29
hate using DMF as a solvent but there is
00:03:31
some chemistry that just tends to need
00:03:34
DMF to work well so it's not my first
00:03:36
choice I would probably put it into s
00:03:38
tier because I definitely have a grudge
00:03:40
against dimethyl formamide and I
00:03:42
wouldn't work with this if I didn't have
00:03:43
to you might like acetic acid now we're
00:03:46
not talking about that wimpy 5% that you
00:03:48
might be putting on your salad we're
00:03:49
talking 100% acetic acid glacial acetic
00:03:52
acid why is it glacial because it
00:03:55
freezes it also stings you on contact
00:03:57
and it stays behind when you try and
00:03:59
evaporate it
00:04:00
it's pretty unfortunate because acetic
00:04:02
acid is actually a pretty good solvent
00:04:03
for doing a lot of chemistry if I had to
00:04:06
choose between doing a reaction in
00:04:07
acetic acid and DMF though I would
00:04:09
probably choose DMF even though acetic
00:04:11
acid is less toxic I would just be
00:04:13
worried about putting most chemicals
00:04:15
into a pure acid solvent because acid
00:04:17
mediated chemistry might occur overall
00:04:20
acetic acid isn't one that have too much
00:04:22
of a grudge against but when that smell
00:04:24
just smacks you in the face so hard it
00:04:26
makes you want to take a break from the
00:04:27
lab for a few hours so for that reason
00:04:29
reason I'm going to put acetic acid into
00:04:31
a tier a for acetic acid another solvent
00:04:34
of note is hexo isopropanol despite my
00:04:36
grudges against this chemical I think
00:04:38
it's a pretty good solvent it's pretty
00:04:39
good for doing chemistry under
00:04:41
relatively mild conditions although it's
00:04:43
really volatile as it has a low boiling
00:04:45
point but often times a little bit of
00:04:47
hexor isopropanol will remain this is
00:04:49
because it forms extremely strong
00:04:51
hydrogen bonds with hydrogen bond
00:04:53
acceptors if that wasn't bad enough it's
00:04:55
extremely toxic as this can get
00:04:57
metabolized into hexif floro acetone
00:04:59
which is a teratogen hexif floro
00:05:01
isopropanol can cause severe respiratory
00:05:03
and systemic effects if that wasn't bad
00:05:06
enough it's also probably the most
00:05:07
expensive solvent on this list so for
00:05:09
all of those reasons we're going to put
00:05:11
it into s tier even though it's an S
00:05:13
tier solvent as well I have a grudge
00:05:15
against it there was this one time I was
00:05:17
making this compound I'll include what
00:05:18
it looked like here and I could not
00:05:20
remove the last bit of hexif floro
00:05:21
isopropanol from this for the life of me
00:05:24
what I ended up doing was I added
00:05:25
methanol to it and evaporated it over
00:05:27
and over and over until the peak in the
00:05:29
NMR for the hfip was almost gone
00:05:32
completely but I could never fully get
00:05:33
rid of it similar to water we have
00:05:35
ethylene glycol ethylene glycol is a
00:05:38
terrible solvent to work with because
00:05:39
it's so viscous and it has a very high
00:05:42
boiling point so that makes it
00:05:43
challenging to remove the main type of
00:05:45
reaction that you'll see done in
00:05:46
ethylene glycol is probably a wolf
00:05:48
kishner reduction but if you have any
00:05:50
other reactions that you like doing in
00:05:52
ethylene glycol make sure you leave a
00:05:53
comment down below one of the downsides
00:05:55
of ethyling glycol is if it's consumed
00:05:57
it gets converted in the body into
00:05:59
oxalic acid which is highly toxic if
00:06:01
ingested leading to metabolic acidosis
00:06:03
renal failure and central nervous system
00:06:06
effects while this compound is less
00:06:08
hazardous by inhalation or skin contact
00:06:10
it's still harmful you can find ethylene
00:06:12
glycol and antifreeze but it's still not
00:06:14
a great solvent to work with in most
00:06:16
cases High viscosity high boiling point
00:06:18
and high toxicity makes this a very
00:06:20
undesirable choice this is another a
00:06:23
tier solvent that I absolutely have a
00:06:25
grudge against a similar looking
00:06:26
molecule is d chloroethane d
00:06:28
chloroethane is an extremely toxic
00:06:30
solvent and it's a known carcinogen
00:06:33
these two chloride groups can easily be
00:06:34
kicked off of the molecule when part of
00:06:36
your body reacts with it it can cause
00:06:38
liver kidney and lung damage inhalation
00:06:41
can cause central nervous system effects
00:06:43
and long-term exposure may lead to
00:06:44
cancer in addition because of the
00:06:46
chlorines on the molecule it ends up
00:06:48
adding to Ozone depletion this is mostly
00:06:51
through emissions from Southeast Asia
00:06:52
and we'll be talking more about this
00:06:54
topic in an upcoming video about ozone
00:06:56
depletion it's not my first choice it's
00:06:58
highly toxic and every time worked with
00:07:00
it I was pretty scared about getting it
00:07:01
on my skin so for that reason we're
00:07:03
going to put D chloroethane into B tier
00:07:05
it's still pretty scary overall but it
00:07:07
has good properties as a solvent so I
00:07:08
don't have too much of a grudge against
00:07:10
it if it's given me cancer it hasn't
00:07:11
happened yet now what would happen if we
00:07:13
took dichloroethane and reacted it with
00:07:15
ethylene glycol we would get dioxane but
00:07:18
dioxane can also be made for methylene
00:07:19
glycol directly one of the downsides of4
00:07:22
dioxane is its tendency to freeze close
00:07:24
to room temperature it also forms
00:07:26
explosive peroxides and it's a possible
00:07:29
carcinogen in humans one of the
00:07:31
downsides to 14 dioxine is that when
00:07:33
you're doing separations it might not be
00:07:35
clear whether your 14 dioxine is in the
00:07:37
aquous or organic layer or more likely
00:07:39
both this can be really frustrating when
00:07:41
you're doing purifications because if
00:07:43
there's a lot of this in the aquous
00:07:44
layer it might dissolve some of your
00:07:46
compounds into that layer as well
00:07:48
another pain point that I have quite
00:07:49
literally with one for dioxine is it
00:07:51
smells like spicy diethyl ether and not
00:07:53
the good kind of spicy some inorganic
00:07:55
chemists will be preparing complexes and
00:07:57
often times thf or one for dioxine are
00:08:00
included in the crystal structure this
00:08:02
might be desirable if you're trying to
00:08:03
get crystals for a publication but it
00:08:05
might be really annoying if it's
00:08:07
disrupting your complexes and you want
00:08:09
to build a very specific Lian system one
00:08:11
for dioxane again not my first choice
00:08:13
I'd probably put it into B tier overall
00:08:16
I do have a grudge against it it does
00:08:17
form peroxides but it still evaporates
00:08:19
relatively easily and as long as you're
00:08:21
not doing super cold chemistry it's
00:08:23
probably well suited for 14 dioxine
00:08:25
acetone acetone is a pretty good solvent
00:08:28
the downside of acetone is it reacts
00:08:30
with a lot of acids and bases and it's
00:08:32
also missible with water again that
00:08:34
means if you're doing an extraction
00:08:35
you're going to have to be careful where
00:08:36
your aquous in organic layers are and
00:08:39
you might need to use a large excess of
00:08:40
solvent like diethylether or D
00:08:42
chloromethane to make sure that you
00:08:43
extract all of your product acetone can
00:08:46
be an okay solvent for some alation
00:08:48
reactions but often times you see DMF
00:08:50
used instead despite these issues
00:08:52
acetone is fairly liked as a solvent so
00:08:55
I think we can put it into F tier
00:08:56
because this is one of the best solvents
00:08:58
that we have overall when when I think
00:08:59
about how much glassware I've washed
00:09:01
with acetone I imagine that I've
00:09:03
probably used at least 400 L of acetone
00:09:06
washing stuff in my time as a chemist
00:09:08
that's a lot of acetone just don't go
00:09:10
drinking any of it and that applies to
00:09:11
all of these solvents for that matter
00:09:13
similar to DMF we have DMSO DMSO isn't
00:09:16
toxic like DMF and some medications are
00:09:18
even dissolved in DMSO so that the drugs
00:09:20
can be absorbed more easily DMSO is the
00:09:22
solvent you go to when your compounds
00:09:24
won't dissolve in anything else much
00:09:26
like DMF it has a really high boiling
00:09:28
point and it's compatible with sodium
00:09:30
hydride as I mentioned earlier another
00:09:32
downside to DMSO is it has a really foul
00:09:34
smell likely due to some impurities
00:09:36
present and if you get simp on your skin
00:09:38
apparently it makes you smell like
00:09:39
garlic for days I haven't tried this yet
00:09:41
but if you have any garlic smell stories
00:09:43
I'd love to hear more down in the
00:09:44
comments DMSO is also hard to remove in
00:09:47
extractions since it tends to be
00:09:49
missable with almost anything but it
00:09:51
isn't missible with diethylether so it's
00:09:53
possible to do extractions from an
00:09:54
aquous layer containing DMSO using
00:09:57
diethyl ether but a small amount of it
00:09:59
will still get transferred to The Ether
00:10:00
layer and it's often necessary to do
00:10:02
column chromatography to remove the last
00:10:04
traces of DMSO overall chemists hate
00:10:07
working with DMSO so we can put it into
00:10:09
s tier which is appropriate s for
00:10:11
sulfoxide one of my biggest Grudges on
00:10:14
this whole list is definitely pyodine
00:10:16
sometimes purine is used as a solvent
00:10:18
and when you use that much purine you
00:10:20
develop a hatred for purine it smells
00:10:22
terrible and I've heard a lot of rumors
00:10:24
from chemists saying that it's
00:10:25
teratogenic in men meaning that it would
00:10:27
cause birth defects but I haven't been
00:10:29
able able to find any science backing
00:10:30
this up yeah like you actually have to
00:10:32
go out of your way to be that stupid on
00:10:34
the topic than you would just spending a
00:10:36
couple of seconds looking it up purine
00:10:38
also has a really high boiling point and
00:10:40
typically the only way that I've found
00:10:41
to remove it completely is to add toine
00:10:43
and evaporate down my compound over and
00:10:45
over until no pyodine smell is left
00:10:48
column chromatography often does a
00:10:49
pretty good job of removing purine but
00:10:51
if you have relatively non-polar
00:10:53
compounds the pine May calute and come
00:10:55
off of the column at the same time as
00:10:57
your product meaning that chromatography
00:10:59
didn't do any separation which is like
00:11:01
the one thing it's supposed to do I
00:11:03
think the only form of Separation that
00:11:04
chromatography really achieves is
00:11:06
separating you from your friends and
00:11:07
family purine is Toxic by ingestion
00:11:10
inhalation and skin contact it can cause
00:11:12
liver and kidney damage and is
00:11:14
irritating to the respiratory tract and
00:11:16
skin it also has this disgusting fishy
00:11:18
smell that I absolutely hate and no
00:11:20
matter how well I would seal my bottles
00:11:22
of purine I would always smell pyodine
00:11:24
whenever I open the cabinet in our lab I
00:11:27
hate purine it can go right into EST
00:11:29
here it does still have some uses as a
00:11:31
solvent it's a little bit polar which is
00:11:32
nice and the lone pair on the nitrogen
00:11:34
can help it form leis complexes it can
00:11:37
act as a ligan and it can also scrub
00:11:39
bases from a reaction I definitely have
00:11:41
a grudge against purine you might not
00:11:43
have a grudge against propionitrile but
00:11:45
you'd be surprised to hear that it's
00:11:46
about as toxic as hydrogen cyanide often
00:11:48
times people use propionitrile when
00:11:50
aceton nitr fails for their chemistry
00:11:52
aceton nital is nowhere near as toxic as
00:11:55
hydrogen cyanide but surprisingly
00:11:56
propionitrile is this is why it's always
00:11:58
important important to look at the
00:11:59
safety data sheet of the chemicals
00:12:01
you're working with before working with
00:12:03
them especially the first time you work
00:12:04
with them let's say Jimmy goes to the
00:12:06
lab if your name's Jimmy I'm sorry for
00:12:08
calling you out if your name's Jimmy and
00:12:10
you've worked with propionitrile this
00:12:11
story literally is you you work with
00:12:13
this you get a bit of it on your arm you
00:12:15
think nothing of it you go home if you
00:12:16
don't want to be in the next chubby emu
00:12:18
video you better read your safety data
00:12:20
sheets the ld50 of propit trial is 39 mg
00:12:24
per kg that's pretty potent for
00:12:26
reference sodium cyanide has an ld50 for
00:12:29
rats of about 6.4 mg per kilg while the
00:12:32
ld50 in rats for aceton nitr is
00:12:36
2,460 mg per kilogram so propan nitr is
00:12:40
actually quite toxic for that reason I
00:12:42
will always have a permanent grudge
00:12:43
against propan nitr since it's so frakin
00:12:46
toxic it can also go right into s tier
00:12:49
last but not least we have diisopropyl
00:12:51
ether I haven't had the pleasure or
00:12:53
displeasure of working with diisopropyl
00:12:55
ether but because of these two CHS right
00:12:57
adjacent to this oxygen this compound
00:12:59
has a propensity to form peroxides this
00:13:02
is probably the most notorious peroxide
00:13:04
forming chemical in the entire research
00:13:05
lab when peroxides start forming because
00:13:08
it's a chain reaction it gets faster and
00:13:10
faster and faster and there is no
00:13:12
shortage of horror stories where an old
00:13:14
bottle of this was discovered in a lab
00:13:15
completely caked in white crystals if
00:13:18
you see any solvent which could form
00:13:19
peroxides caked in white crystals don't
00:13:22
touch it let your supervisor know and
00:13:24
make sure that eh&s or a bomb team are
00:13:27
able to deal with it since it's di ISO
00:13:29
propy ether I think we can put it into D
00:13:31
tier D cuz you might die so these were
00:13:33
some of the solvents that I have strong
00:13:34
grudges against I would definitely
00:13:36
prefer to wash stuff with acetone than
00:13:38
with DMF and if I could avoid using
00:13:40
hexor isopropanol I would definitely try
00:13:43
to avoid it as you can see safety
00:13:45
considerations are always something
00:13:46
worth considering when you're doing
00:13:48
chemistry you should read into the
00:13:50
chemicals that you're working with
00:13:51
before working with them to make sure
00:13:53
that your next experiment isn't your
00:13:54
last experiment hopefully this isn't the
00:13:56
last video of mine you watch either
00:13:58
thanks for watching and I hope you have
00:13:59
a great day
