Carbon-Carbon and Carbon-Heteroatom Bond Formation Reactions
Sp3 is when there are 4 single bonds attached to a C
Sp2 is when there is a double attached to a C
Sp is when there is a triple bond attached to a C
Lets get into the reactions:
Nucleophilic substitution of haloalkanes with cyanide ions
Reagent: KCN or HCN dissolved in ethanol/water mixture under heating/reflux conditions results in a Nitrile. The reaction increases the length of the carbon chain by one carbon.
SN1 mechanisms( 2 steps ) First bond breaks, then CN attacks
Addition of hydrogen cyanide to carbonyls to form hydroxynitriles
Reagent: NaCN and dilute sulphuric acid in room temp and pressure conditions. The H2SO4 provides the H+(acidic hydrogens) for the 2nd step after the CN attacks.
Friedel-Crafts Alkylation
Reagent: chloroalkane in the present of anhydrous AlCl
(strong lewis acid) catalyst under heat/reflux
Turning a benzene into an alkylbenzene. Chloroalkane can be used as RCl where R is any alkyl group and the electrophile is R+
Benzenes are electronic so they need an electrophilic attack instead of a nucleophilic attack
Reimer-Tiemann reaction
Phenols is warmed with chloroform and aqueous alkali to obtain ortho or para-formylated product. The intermediate is Dichlorocarbene.
Base needs to go from aqueous to organic conditions
Enolates
LDA is really basic. NAH, NaOH NaOEt are all used to generate a negative charge.
alpha-alkylated product
Kinetic means formed very quick, Kinetic Enolates
NaOH is used to hydrolyze in the second alkylation it turns the COOEt into COOH then the heat turn that into COO- and be removed.
Acetoaceticester synthesis
Next Topic is Stork Enamine reaction, that stopped at slide 20.
Alkylting the alpha carbon, Mainly uses a cyclic compound. Enamines are hghly reactive. Need to have at least one alpha hydrogen. 1,4 additionproducts can alsooccur
Aldol Condensation
Need to have at least one alpha hydrogen on the carbonyl compounds. Enolate has an alpha hydrogen, it is just written in anither firm. Whichever doesnt have the alpha carbon turns into hydroxy group. Dont worry about the acidic reaction slide for this.
Needs heat to
Crossed Aldol Condensaton
Aldol reactions can be used to make alcohols, staright chain alcohols.
Claisen Condensations
Uses 2 esters OR 1 ester and carbonyl, should have one alpha carbon. Only one ester can have an alpha carbon
Dieckmann Condensation
It is intramolecular, meaning it happens in the same molecule.
Knoevenagel Condensation reaction
Using an active methylene compound that has activation groups. Nucleophilic addition reaction. Carbonyl compound is also used.
Wittig Reaction
Makes an alkene. If the R group is ewg it become more stable and less reactive and it will create E alkenes. But if it is nons
Horner-wadsworth
Phophsite is easy to remove through a water reaction. This is always E selective
Michael Addition
Micahel donot and micahel acceptor(needs to be electron deficient). 1,4 Addition. There is no elimination in this reaction
Aza Micahel Addition
Uses an amine to complete reaction
Robinson Annulation
RA MA AC - acronym you cn use to remeber
Diels -alder reaction
4+2Cycloaddition
Happens between diene and dienophile “phile” means loving. The Dienophile should be electron deficient. Its ideal to have a edg on the diene and weg on the dienophile
Conditions: the dienophile must be in cis confirmation.
Sterochemistry is still conserved
Regioselectivity - When there is a EDG is onthe middle itforme a 1,4 and if its on the first carbon it makes 1,2. remember 2,1,4 and 1,1,2
Only uses heating conditions.
Make a list of reactions with conditions. With te reagensts