Org. Chemistry Reactions Flashcards
Heating ALKENE with H2 gas and Pt/Ni catalyst:
Alkane
Producing ALKANE from ALKENE
Hydrogenation by heating ALKENE with H2 gas and Pt/Ni catalyst
Complete combustion of ALKANE
… + O2 -> CO2 + H2O
Incomplete combustion of ALKANE
… + O2 -> CO + H2O
Producing HALOGENOALKANE from ALKANE
Free-radical substitution using UV light
Catalytic removal of carbon monoxide using oxygen
2CO + O2 -> 2CO2
CO oxidised into CO2
Catalytic removal of carbon monoxide and nitrogen
2CO + 2NO -> 2CO2 + N2
NO/NO2 reduced into N2
Catalytic removal of unburnt ALKANES
CnH2n+2 + (3n+1) [O] -> nCO2 + (n+1) H2O
Oxidation of alkane into CO2 and H2O
What does homolytic fission form?
2 free-radicals
What does heterolytic fission form?
1 cation and 1 anion
Producing halogenoalkane from ALKENE
Electrophilic addition of hydrogen halide (HX) or halogen (X2)
Process of electrophilic addition of hydrogen halide (HX) to ALKENE
- Electrons in the double bond attack the partially positive hydrogen (electrophile), forming C-H bond by donating the electrons.
- The negatively charged X (nucleophile) attacks the carbocation formed, forming C-X bond with the most substituted carbon atom.
Product: CnH2n+1X
Process of electrophilic addition of halogen (X2) to ALKENE
- Double bond induces a dipole on the X2 by repulsing electrons away from the closer X.
- Double bond electrons attack the partially positive X, forming C-X bond.
- Negatively charged X left behind attacks the carbocation formed, forming C-X.
Product: CnH2nX2
Reaction between alcohol and hydrogen halide (HX)
Substitution.
Forms halogenoalkane (CnH2n+1X) and water.
Reaction between alcohol and PCl3, heated
Substitution.
Forms halogenoalkane (CnH2n+1X) and phosphorus acid (H3PO3)
Reaction between alcohol and PCl5
Substitution.
Forms halogenoalkane (CnH2n+1X), hydrochloric acid (HCl) and phosphorus oxychloride (POCl3).
Reaction between alcohol and SOCl2
Substitution.
Forms halogenoalkane (CnH2n+1X), hydrochloric acid (HCl) and sulphur dioxide (SO2)
Define primary, secondary and tertiary halogenoalkane
Primary: carbon bonded with 2 hydrogen
Secondary: carbon bonded with 1 hydrogen
Tertiary: carbon bonded with no hydrogen
Reaction between halogenoalkane and NaOH(aq)
Substitution (hydrolysis).
Halogen atom replaced with OH.
Forms: alcohol and negatively charged halogen
Reaction between halogenoalkane and AgNO3(aq)
Substitution (hydrolysis).
Halogen atom replaced with OH.
Forms: alcohol and negatively charged halogen
Does NaOH(aq) react faster than AgNO3(aq) with halogenoalkane? Explain.
Yes, NaOH reacts faster because it is an alkali that donates OH- easier than water, which is only partially negative.
Reaction between halogenoalkane and ethanolic KCN
Substitution.
Halogen atom replaced by CN.
Forms nitrile and negatively charged halogen.
Reaction between halogenoalkane and ethanolic NH3 in excess
Substitution.
Halogen atom replaced by NH3, forming alkylammonium and negatively charged halogen.
One hydrogen atom is attacked by nucleophilic halogen, forming alkylamine and hydrogen halide.
Reaction between halogenoalkane and ethanolic NaOH, heated
Elimination.
Heterolytic fission between C-X, forming negatively charged Br.
Forms alkene, sodium halide and water.
Process of SN2 in halogenoalkane
Occurs in primary halogenoalkane.
1. Nucleophile attacks partially positive carbon C-X, electrons from the bond move to X.
2. Forms an intermediate, bond with X breaks and bond with nucleophile forms.
3. Produces alcohol and negatively charged halogen.
Process of SN1 in halogenoalkane
Occurs in tertiary halogenoalkane.
1. C-X breaks heterolytically, forming a carbocation and a negatively charged halogen
2. Nucleophile attacks carbocation
3. Forms alcohol and negatively charged halogen
Precipitate of AgNO3 added to Cl
AgCl, white precipitate, appears slowest
Precipitate of AgNO3 added to Br
AgBr, cream precipitate, appears slightly slow
Precipitate of AgNO3 added to I
AgI, yellow precipitate, appears the fastest
Producing ALKENE from halogenoalkane
Elimination.
Heated with ethanolic NaOH.
Produces alkene, water and sodium halide
Producing ALKENE from alcohol
Dehydration.
Heated with Al2O3 powder.
Produces alkene and water
Producing ALKANE from ALKENE
Electrophilic addition (hydrogenation)
Heated with Pt/Ni catalyst.
Producing alcohol from ALKENE
Electrophilic addition (hydration)
Heated with H3PO4 and steam
Producing halogenoalkane (CnH2n+1X) from ALKENE
Electrophilic addition.
At room temperature, with hydrogen halide
Producing halogenoalkane (CnH2nX2) from ALKENE
Electrophilic addition.
At room temperature, with halogen