6d Flashcards
okay describe this auxiliary we keep talking about lols
okay so think pentagon
qith a carbonyl on the top
a dashed isopropyl,, aka a Y coming from the bottom left but the Y is dashed
then u have an N on top left where the other moelcule attaches to
and u have an O on the top right
okat so normally when u have a moelcule and that auxiliary,, when u deporotnate the molecule and get a (-) what face does the electrophile get added to
it gets added to the front face
bc the dashed Y on the auxiliary blocks the back face
when u have the auxiliary and a carbonyl // enolate on the other moelcule,, what happens between them
the O’s are associated via a Metal!! aka from the thing that deprotonates the thing.
and this locks the auxiliary and the molecule in that rotation bc it prevents the bond between then rotating!!!
and ofc the double bond of the enolate also restrict rotation
when were drawing the chair structure,, what do we need to remember
the back side of the cyclochair points downwards,,
so u need to acc look at the previous structures and asee if theres any groups ,, aka see if the enolate was Z or E,, and then use this to place groups axially or equatorially.
if an Me and O- were Z aka same side,, and the O is pointing down bc thats the way cyclohexane is,,the Me would also try point down!!
how do we make an aldol reaction when we have the auxiliary
u need to associate the O of the aldehyde and the O of the enolate,, not the O of the auxiliary
this allows the auxiliary to rotate and so it does,, this makes the Y wedged.
the O’s associate and the aldol reaction occurs,, but the aldehyde is added to the back of the moelcule,, bc the auxiliary is wedged when it rotates!!!
u then rotate the bond so the aldehyde bit is part of the main bit of the molecule,, and bc u have a Z enolate,, youll have a syn product,, so the Me and OH will both be dashed
Z enolate gives what
syn aldol product
E enolate gives u
anti aldol product
whats a hydrazone
an immine type thing
so C=N
but the N is also connected to another N!!!!!!!
whats special about hydrazone
the hydrogens on the R groups on the C \are very acidic
bc if u think about it its kinda like a carbonyl bc O and N are very similar
so its kinda like making an enolate but when u have a hydrazone u kinda just deprotonate the acidic H’s and then leave it as a (-)
what do u do with a deprotonated hydrazone
u can use it to attack electrophiles!!!!!
the chiral centre // (-) of the hydrazone does what
it dictates the stereochemistry of the chirality of the E.
so like when the electrophile is added to the hydrazone, the hydrazone decides if the E will be added dashed or wedged!!!!
whats a si face
the side of the carbonyl that has S config
whats a re face
the side of the carbonyl that has R config
what is a diels alder reaction all about
its about a diene and an alkene!!!
ik yk it girl but whats a diene again and what types are there
diene is 2 double bonds in a molecule !!!
app they dont need to be conjugated
what happens in a diels alder reaction
basically the diene goes about the alkene so that theyre p orbitals can have cnstructive overlap
and then they kinda lower down onto eachother and form a ,, normally cyclic molecule!!!
u need to draw the curly arrows,, so the alkene attacking the end of the diene couble bond,, and that conjugating onto the single bond between the diene double bonds,, and then the last diene double bond attacking the space between then alkene and the diene
then u kinda overlap these bits to form a new molecule
2 non chiral molecules react to give what
2 non chiral moelcules react to give enantiomers!!!!!!!
so both things dashed or both things wedged!!!
we dont rlly get one dashed one wedged
when we have the carboxylic acid diene and alkene for the diels alder reaction,, do the carboxylic acids like to be ontop of eachother
yes
its a favourable reaction somehow. !!!!
in the diels alder reaction,, whats the endo product
the endo product is the one where u have both dashed or both wedged
aka the couple are both entering the building
when both COO2H are wedged or dashed.
in the diels alder reaction,, whats the exo product
when one COO2H is dashed and one is wedged!!!
