Question | Answer |
benzene | an organic chemical compound with the molecular formula C6H6. It is sometimes abbreviated Ph–H. It is a colorless and highly flammable liquid with a sweet smell and a relatively high melting point |
aromaticity | chemical property in which a conjugated ring exhibit a stabilization stronger than would be expected by the stabilization of conjugation alone. It can also be considered a manifestation of cyclic delocalization and of resonance |
huckel's rule | A cyclic ring molecule follows this rule when the number of its π-electrons equals 4n+2 where n is zero or any positive integer |
molecular orbital theory | is a method for determining molecular structure in which electrons are not assigned to individual bonds between atoms, but are treated as moving under the influence of the nuclei in the whole molecule. |
most characteristic aromatic compound reaction | Electrophilic aromatic substitution or Ar-H in Halogenation, Nitration, Sulfonation, Alkylation, and Acylation reactions |
three general steps to electrophilic aromatic substitution | 1. Generation of electrophile(E+)2.Attack of electrophile on ring to give Carbocation intermediate(C+) 3. Proton transfer to a base(Base-H) |
intermediate during chlorination and bromination of aromatic compounds | resonance stablized cation intermediate where C+ moves around the ring and H + Cl bonded to same carbon of the ring |
reagents for the nitration of benzene | HNO3 with H2SO4 where the electrophile is NO2+ formed by treating HNO3 with H2SO4 |
reagents for the sulfonation of benzene | H2SO4 where electrophile is HSO3+ |
why is the order for electrophilic substitution important | because there are three isomeric products possible that may be ortho, meta, or para position to the first group substituted not only orientation is affected but so is the rate of further substitution |
most activating substituents to further electrophilic aromatic substitution | Ortho-Para(strongly activating)-NH2,-NHR,-NR2,-OH,-OR Meta(strongly deactivating)-NO2,-NH3+,-CF3,-CCl3 |
addition of grignard reagents in aldehydes and ketone | grignard reagent R-MgBr + formaldehyde H(C=O)H in ether gives a magnesium alkoxide R-CH2(O-MgBr+) then reacts with HCl and H2O to create R-CH2OH(primary alcohol)plus Mg(2+)Other aldehydes create secondary alcohols and ketones create tertiary alcohols |
grignard reagent | a compound with a carbon-magnesium bromide bond or RMgBr |
formaldehyde + grignard reagent plus hydrolysis in aqueous acid yields | primary alcohol |
carbonyl carbon + what makes hemiacetal | alcohol oxygen adds to carbonyl carbon and Hydrogen adds to carbonyl oxygen |
carbonyl oxygen + what makes hemiacetal | alcohol oxygen adds to carbonyl carbon and Hydrogen adds to carbonyl oxygen |
hemiacetal formation versus acetal formation | acetal formation is done by excess alcohol used as reagent and solvent or by dehydration of H2O |
addition of ammonia to aldehydes and ketone | ammonia NH3 creates R-CH=NH and H2O |
addition of amines to aldehydes and ketones | creates an imine(Schiff base) and water where R-(C=O)H + H2N-R' create R-CH=N-R' plus H2O |
addition of alpha-halogenation to aldehydes and ketones | |
common oxidizing agents for aldehydes to carboxylic acids | chromic acid(H2CrO4),molecular oxygen(O2),Silver Ion(Ag2O with THF,H2O,NaOH),Tollens' reagent(AgNO3 H2O + NaOH to create Ag2O then add NH3 H2O to create Ag(NH3)2+NO3-, Hydrogen Peroxide(H2O2) |
comman reactants and catalysts during a catalytic reduction of aldehydes and ketones into alcohols primary and secondary | transition metal catalyst of Palladium, Platinum, nickel, or rhodium 25-100 degrees celsius and 1-5 atm pressure C=C are also reduced |
comman reactants and catalysts during a metal hybride reduction | NaBH4(only aldehydes and ketones carbonyl groups) and LiAlH4(also carboxylic acid carbonyl groups) Where H2 and Rh only do C=C solvent includes Ch3OH methanol CH3CH2OH ethanol |
reagents used to oxidize aldehydes and ketones to carboxylic acids | |
reactants to reduce aldehydes and ketones to alcohols | |
reactants to oxidize alcohols to aldehydes and ketones | |
important characteristics of PCC pyridinium chlorchromate reagent during the oxidation of alcohols | |
Decarboxylation reactions | Beta-Ketoacids yields elimination of -COOH plus CO2;Beta-Dicarboxylic acids yields carboxylic acid and CO2 |
soap hydrophobic and hydrophillic | |
Oxidation at a Benzylic Position | a benzylic carbon bonded to at least one hydrogen is oxidized to a carboxyl group |
Oxidition of benzene | yields aromatic dicarboxylic acid using K2Cr2O7 and H2SO4 |
Chlorination/Bromination of Benzene | the electrophile is a halonium ion, Cl+ or Br+, formed by treating Cl2 or Br2 with AlCl3 or FeCl3 |
Chlorination/Bromination of Benzene | yields Halobenzene plus HX using AlCl3 or FeCl3 |
Nitration of HaloBenzene | the electrophile is the nitronium ion, NO2+, formed by treaing nitric acid with sulfuric acid |
Nitration of HaloBenzene | yields -NO2 at ortho and para positions plus H2O |
Sulfonation of Benzene | the electrophile is HSO3+ |
Sulfonation of Benzene yields | Ar-SO3H plus H2O using H2SO4 |
Friedel-Crafts Alkylation of Benzene | the electrophile is an alkyl carbocation formed by treating an alkyl halide with a Lewis Aci |
Friedel-Crafts Alkylation of Benzene R-Cl | yields Ar-R plus HCl using AlCl3 |
Freidel-Crafts Acylation | The electrophile is an acyl cation formed by treating an anyl halide with a Lewis acid |
Freidel-Crafts Acylation | Benzene plus chlorinated aldehyde (CH3C=OCl)with AlCl3 |
Benzene plus chlorinated aldehyde (CH3C=OCl)with AlCl3 yields | ArC=OCH3 plus HCl |
Alkylation using an alkene on benzene | the electrophile is a carbocation formed by treating an alkene with H2SO4 or H3PO4 |
para-Methyl-phenol plus 2 (CH3)2C=CH2 with H3PO4 yields | diortho isopropyl(C(CH3)3) para-methyl phenol |
Alkylation using an alcohol on benzene | the electrophile is a carbocatio formed by treating an alcohol with H2SO4 or H3PO4 |
benzene plus isopropylalcohol with H2SO4 yields | isopropyl benzene plus water |
acidity of phenols | phenols are weak acids |
phenol plus water yields | phenoxide ion ArO- plus H3O+ pka=9.95 |
phenol plus water | substitution by electron-withdrawing groups, such as teh halogens and the nitro group, increases the acidity of phenols |
phenols with strong bases | water-insoluble phenols react quantitatively with stron bases to form water-soluble salts |
phenols with strong bases(NaOH) yield | Sodium phenoxide(ArO-Na+) and water |
formaldehyde with grignard reagent(C6H5MgBr) followed by hydrolysis(H2O) in aqueous acid(HCl)yields | primary alcohol C6H5C(OH)HCH3 |
treatment of any aldehyde besides formaldehyde with Grignard reagent, hydrolysis, and aqueous acid yields | secondary alcohol |
Treatment of ketone with a grignard reagent yields | tertiary alcohol |
Ketone(CH3(C=O)CH3) plus grignard reagent(C6H5MgBr)+ H2O with HCl yields | C6H5(COH)(CH3)2 or another way of saying it as (Ar-COH(CH3)2) |
Addition of Alcohols to Form Hemiacetals | Hemiacetals are only minor components of an equilibrium mixture of aldehyde or ketone and alcohol, except where the -OH and C=O groups are parts of the same molecule and a five- or sic-membered ring can form |
Addition of Alcohols to form hemiacetals | 4-hydroxypentanal CH3C(OH)HCH2CH2(C=O)H forms equilibrium more towards hemiacetal with methyl group on one end and alcohol on the other and an oxygen conecting the 4 rings of carbon between the methyl and alcohol groups |
addition of alcohols to form acetals | cyclopentane=O plus HOCH2CH2OH catalyzed by acid H+ equilibrium yield to cyclopentane with two oxygens connecting two CH2 in a cyclical manner plus water |
Addition of Ammonia and Amines | the addition of ammonnia or a primary amine to the carbonyl group of an aldehyde or a ketone forms a tetrahedral caronyl addition intermediate. Loss of water from this intermediate gives and imine(schiff base) |
cyclopentane=O plus H2NCH3 catalyzed with acid(H+) equilibrium yields | cyclopentane=NCH3 plus H2O |
Reductive Amination to Amines | the carbon nitrogen double bond of an imine can be reduced by hydrogen in the presence of a transition metal catalyst to a carbon-nitrogen single bond |
cyclohexane=O plus H2N-cyclohexane dehyrates(-H2O) into | cyclohexane=N-cyclohexane intermediate |
cyclohexane=N-cyclohexane intermediate adding H2/Ni to form | cyclohexane-NH-cyclohexane |
Keto-Enol tautomerism | the keto form generally predominates at equilibrium |
Oxidation of aldehyde to a carboxylic acid | the aldehyde group is among the most easily oxidized functional groups. Oxidizing agens include H2CrO4, tollens' reagent, and O2 |
Benzene ring with -C(=O)H and adjacent -OH group plus Ag2O with THF,H2O, NaOH then H2O, HCl yields | benzene ring with carboxylic acid and adjacent alcohol plus Ag |
Catalytic Reduction of a carbonyl group | in an aldehyde or ketone to a hydroxyl group is simple to carry out and yields of alcohols are high |
cyclohexane=O plus H2 with Pt at 25 degrees celsius and 2 atm yields | cyclohexane-OH |
Metal hydride reduction or carbonyl group | both LiAlH4 and NaBH4 reduce the carbonyl group of an aldehyde or a ketone to an hydroxyl group. They are selective in that neither reduces isolated C=C only C=O |
cyclohexene=O with NaBH4 and H2O yields | cyclohexene-OH C=C in not reduced on C=O |
acidity of Carboxylic acids values of pka | for most unsubstituted aliphatic and aromatic carboxylic acis are within the range from 4 to 5. |
Substitution by electron-withdrawing groups to carboxylic acids acidity is | increased pka decreases |
Reaction of Carboxylic Acids with Bases forms | water-soluble salts with alkali metal hydroxides, carbonates, bicarbonates, ammonia, and amine bases |
Ar-COOH + NaOH with H2O yields | Ar-COO-Na+ plus H2O |
Reduction of Carboxylic Acid with LiAlH4 and H2O | reduces carboxyl group to a primary alcohol basically hydrogenating the carbonyl group |
cyclopentene-COOH plus LiAlH4 and H2O yields | cyclopentene-CH2OH |
Reversible Fischer-Esterification | Carboxylic Acid + Alcohol and H2SO4 yields ester and H2O |
CH3COOH + HOCH2CH2CH3 equilibrium with H2SO4 environment yields | CH3COOCH2CH2CH3 + H2O |
Making Fischer-Esterification yield ester by | adding excess alcohol reagent |
Conversion of Carboxylic Acid to Acid Chloride by | treating carboxylic acid with thionly chloride SOCl2 |
CH3CH2CH2COOH plus SOCl2 yields | CH3CH2CH2C=OCL + SO2 + HCl |
Decarboxylation of Beta-Ketoacids involves | redistribution of bonding electrons in a cyclic, six-membered transition state |
Cyclohexane(C=O)with adjacent(COOH) warmed yields | Cyclohexane(C=O) changing COOH to CO2 |
Decarboxylation of Beta-Dicarboxylic Acids is similar to | Decarboxylation of B-Ketoacids |
HOOCCH2COOH plus heat yields | CH3COOH plus CO2 |
common oxidizing agents for ketones to dicarboxylic acids | oxidative cleavage via their enol form where C=O gets made into beta-double bonding and C-OH |
common oxidizing agents for ketones to cyclo-COOH to aliphatic HOOC-R-COOH | potassion dichromate and potassium permanganate at higher temps and high concentration of HNO3 nitric acid |