ochem reactions Flashcards
what is the combustion reaction equation?

describe the three steps of free readical halogenation

what is pyrolysis

what is disproportionation

what is the difference between disproportionation and pyrolysis
disproportionation is when a radical transfers a hydrogen atom to another radical producing an alkane and an alkene
What kinds of reactions do alkans undergo?
cumbustion
free radical halogenation
pyrolysis
how do you synthesize alkenes
elimination reaction
what kinds of reactants undergo elimination to get alkenes
alcohols and alkyl halides

catalytic hydrogenation of alkenes

addition of HX to akene

addition of X2 to an alkene
anti addition

adding water to an akene

free radical additions to alkene

hydroboration of alkene

reagent used to oxidize alkenes
potassium permanganate (KMnO4) either hot or cold.
oxidizing alkene with cold dilute KMnO4

oxidation of alkene with hot basic solution of KMnO4
makes carboxylic acids
terminal alkenes become ketone and co2

Ozonolysis of alkene
makes aldehydes and ketones under reducing condtions (Zn/H+ or (CH3)2S)
under oxidizing conditions (H2O2) has same products as hot KMnO4

how can you use ozonolysis to synthesize alcohols
reduce ketone /aldehyde products with mild reducing agent such as NaBH4 or LiAlH4

cycloalkene plus MCPBA
SYN addition

polymerization

two ways to synthesize alkynes
two rounds of elimination of geminal or vicinal dihalide
using an acetylide ion
snthesize alkyne with a dihalide

using an acetylide ion to form an alkyne

how to reduce alkyne and get cis isomer
H2 and lindlers catalyst

how to reduce alkyne and get trans isomer
use sodium in liquid ammonia below -33 degrees C. mechanism=free radical

adding 1 or 2 equivalent of Br2 to an alkyne

describe free radical addition to alkynes
anti markovnikov orientation. reaction product is usually the trans isomer

what product do you get from the hydroboration of an alkyne
syn addition
produces cis alkenes

hydroboration of terminal alkyne

ozonolysis of alkynes
acts just like hot basic KMnO4

halogenation of benzene

sulfonation of benzene

nitration of benzene

how to add -COCH3 to benzene
Acylation (Friedel Crafts Reactions

substituent effects: activator
donate electron density
directs new substituents to ortho and para positions
substituent effects: deactivator
electron withdrawing
meta position
exceptions: halogens are deactivating, but direct to the ortho and para positions
catalytic reduction of benzene rings
only under vigorous conditions: elevated temp and pressure

reduction reactions to make alcohols
what is an example of a strong reducing agent and what is an example of a weak reducing agent, and what do they reduce
LiAlH4 – strong –reduces everything
NaBH4 – weak – reduces aldehydes, ketones, acyl chlorides, but does not reduce esters, carboxylic acids, or amines

phenol synthesis via hydrolysis of diazonium salt

elimination rxn with alcohol

what is required for a substitution reaction with an alcohol
OH is a poor leaving group, must be protonated for SN1 or tosylated for SN2

substitution with tosylated alcohol

conversion of an alcohol to an alkyl halide

oxidation of alcohols with PCC (what is different about PCC?)
PCC is a mild oxidant and is able to partially oxidizes primary alcohols.–stops after primary alcohol has become an aldehyde
behaves normally with secondary alcohols

alcohol + Na2Cr2O7 (what kind of reagent is Na2Cr2O7)
strong oxidzing agent- will fully oxidize primary alcohols to carboxylic acids (secondary to ketones)

what is an even stronger oxidizing agent than Dichromate salt?
Chromium trioxide (CrO3) also called Jones reagent/jones oxidation.

what products do you get from oxidizing phenols?
quinones

williamson ether synthesis

williamson ether synthesis with phenol

synthesis of cyclic ether via sn2

synthesis of cyclic ether with peroxy acid (what is peroxy acid)
proxy acid: general formula (RCOOH
example: mcpba

cleavage reaction–what conditions are required?
vigorous conditions==high temp with HBr or HI
SN1 or SN2 reaction
alcohol products usually react with a 2nd molecule of hydrogen halide to produce alkyl halide

epoxide opening (two types)
acid-catalyzed
base catalyzed

enolization
what are the two isomers called?
two isomers are called tautomers

michael addition

addition raction to carbonyl to make alcohol

hydration rxn of carbonyl

addition of one equivalent of alcohol to aldehyde or ketone
heiacetal or hemiketal formation

addition of two equivalents of alcohol to aldehyde or ketone
acetal and ketal formation

addition of cyanide to carbonyl

condensation reaction with ammonia derivative. what is a condensation reaction?
a condensation reaction is a reaction in which water is lost between two molecules

nucleophilic additions of ammonia derivatives to carbonyls
NH3,
H2NOH
H2NNH2
H2NNHCONH2

aldol formation

aldol condensation

wittig reaction

wolff-kishner reduction

clemmensen reduction

formation of carboxylic acids using organometallic reagents

synthesis of carboxylic acid via hydrolysis of nitriles

nucleophlic acyl substitution to carboxylic acid
same as substitution with carbonyl

reduction of carboxylic acid

formation of an ester from carboxylic acid and alcohol

acyl halide formation from carboxylic acid. what reagent do you react with the carboxylic acid?
thionyl chloride (SOCl2)

decarboxylation reaction, what is required for spontaneous decarboxylation?
requires heat

hydrolysis of acyl chloride

conversion of acyl chloride into ester

conversion of acyl halides into amides

friedel crafts acylation

conversion of acyl halide to corresponding aldehyde. what kind of reagent?
bulky reducing agent
LiAl(O-R)3H (only has one hydride to transfer. this prevents reducing agent from reducing all the way to an alcohol)

synthesis of anhydrides starting with carboxylic acid
condensation of carboxylic acid

synthesis of anhydride from acid chloride
acid chloride plus carboxylate ion

intramolecular anhydride formation

hydrolysis of anhydride
conversion of anhydrider to amides

formation of ammonium carboxylate from anhydride

formation of an ester from anhydride

friedel crafts acylation using anhydride

hydrolysis of an amide

hoffman rearangement
an amide is exposed to br2 and haoh which formes a nitrene results in the rearrangement of the R group bound to the carbonyl and the formation of isocyanate; isocyanate is then hydrolied to form co2 and an amine

reduction of amide

creations of esters from carboxylic acids

hydrolysis of esters

what is saponification and acidification
the process by which fats are hydrolized under basic conditions to produce soaps–acidification of soap regenerates fatty acids

creating an amide from an ester

transesterification

grignard addition to esters
claisen condesnation

ester reduction.
cannot be reduced with weak reducing agents like nabh4

what are phosphate esters

alkylation of ammonia (direct alkylation)

gabriel synthesis: what is it used to accomplish?
converts primary alkyl halide to primary amine

reduction of nitro group

reduction of nitriles

formation of amine from an imine

reduction of amide to amine

exhaustive methylation

glucose esterification

oxidation of monosaccharides. what oxidizing agents do you use
aldoses can be oxidized to aldonic acids by tollens’s or benedicts reagents

glycosidic linkage formation
hemiacetal or hemiaketal sugrs react with alcohol under acidic conditions and form acetals or ketals (carbon with 2 -OR groups)

disacchride formatin
the hydroxyl on the anomeric rbon reat with he hydroxyl of another sugar to form acetals or ketals with1,2 1,4 1,6glycosidic linkages

alpha vs beta glycosidic linkage

peptide bond formation and hydrolysis

tiration of an amino acid
- when adding base, the carboxyl groups lose their protons first; after all of the carboxyl groups are fully deprotonated, the amino groups start to lose thir acidic protons
- two moles of base must be added to deprotonate one mole of most amino acids. the first mole deprotonates the arboxyl group, whereas the second deprotonates the amino group
- the buffering capacity of the amino acid is greatest at or near the pH of the two dissocition constants pka1 and pka2. its buffering capacity is minimal and the graph appears as a vertical line
- some amino acids contain acidic or basic side chains to find the pI of these amino acids, simpling average the two acidic pkas if the side chain is acidic or the two basic pakas if the side chain is basic
- it is possible to perform the itriation in reverse from alkaline pH to acidic pH with the addition of acid; in that case the sequence of events is reversed