NITROGEN CHEMISTRY

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  • Created by: Gretz
  • Created on: 14-06-16 20:48
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  • ORGANIC NITROGEN COMPOUNDS
    • AMINES
      • REACTIONS
        • SMELL. Ammonical to fishy as carbon chain increases
        • WITH WATER AND ITS MISCIBILITY IN IT. Hydrogen bonding occurs making them very soluble. However as chain length increases solubility decreases.
          • Reacts with water similarly to ammonia so reaction, actions as apron on acceptor o form a positive cation and hydroxide ion.
        • WITH ACIDS TO FORM OF SALTS. Ex otherwise reaction and LOSS OF FISHY SMELL.
          • Primary amines are stronger bases than ammonia. To the inductive effect of the alkyl group - donates electrons to increase electron density on nitrogen, so can hold a proton more strongly.
        • FORMATION OF COMPLEX IONS. The whole amine molecule can act as a ligand in the same role as ammonia, both donating a lone pair to the central positive metal ion.
        • WITH ACYL CHLORIDES (ETHANOYL CHLORIDE). produces AMIDES. The lone pair of electrons on the nitrogen of the amine allows it to act as  nucleophle, attacking the delta positive carbon of the CO double bond.
        • TREATMENT WITH HALOGENOALKANES. Go to formations by ammonia/halogenoalkane,ammonia is just replaced with an amine, reacts the exact same way.
        • with NITROUS ACID. make in situ by mixing ice cold solutions of sodium nitrate and HCL acic, mix with the amine in reaction vessel kept in ice water mixture, as temperature must be kept below 5*c. primary amines reduction produces an alcohol (sustitue OH for NH2, NITROGEN AND WATER
      • FORMATION
        • AMMONIA PLUS HALOGENOALKANE. Heat the ammonia under pressure with a halegenoalkane. The ammonia  hydrogen atom/s can be replayed by the ALKYL group of the halegenoalkane.
          • EXCESS AMMONIA/amine
            • Excess ammonia
              • Ammonium salt, and monosubstited amine produced (one hydrogen of ammonia is subd for alkyl group from halogenoalkane. Also evolves HX
            • Excess amine
              • Ammone salt, and new amine produced (one hydrogen of amine is subd for alkyl group from halogenoalkane. Also evolves HX
          • Excess halogenoalkane
            • QUATERNARY AMMONIUM SALT produced. Alkyl group of halogenoalkane substitutes onto every hydrogen of ammonia/amine, and also for a a fourth bond by the lone pair of electrons on the nitrogen, giving a positive cation. The anion of the salt is the halogen ion.
          • Whatever's in EXCESS produces the salt, and the less halogenoalkane, the less substitutions can take place.
        • REDUCTION OF NITRILES. Add lithium tetrahydridoaluminate in dry ether, followed by dilute acid.
      • AROMATIC AMINES (phenyl amines)
        • FORMATION
          • REDUCTION OF NITRO COMPOUNDS. Summary: use TIN and HYDROCHLORIC ACID under reflux. Write equation with H2 and then second product is water. Tin does the reducing, HCL provides the H+ needed for the half equations.
            • 1.   Add  mix of tin and HYDROCHLORIC acid and reflux.
              • 2. Cool flask, NaOH solution added to redissolve initial  Sn(OH)4 PPT .
                • 3. Add water and STeam DISTILATION
                  • 4.SALTING OUT
                    • 5. SOLVENT EXTRACTION
                      • 6. Pellets KOH to dry
                        • 7. DISTILATION,ethoxyethane then phenyl amine
        • WITH NITROUS ACID.HNO2 madi in situ mixing ice cold solutions of SODIUM nitrate and dilute hydrochloric acid
          • BELOW 5*: BENZENE DIAZONIUM CHLORIDE formed with water. include HCL in equation they are stable up to 10*c due to additional stability of benzene ring (why aliphatic diazonium salts are not produced - would be too unstable)
            • Undergoes NUCLEOPHILIC ATTACK because of stong positive charge on benzene diazonium ion. *BEING ATTACKED BY NUCLEOPHILES) NITROGEN gas produced
              • STEAM DISTILATION
                • PHENOL
              • REFLUX WITH KI
                • IODOBENZENE
              • Conc. HCl, CuCl catalyst, reflux
                • chlorobenzene
              • CONC. HBr, CuBr catalyst, reflux
                • bromobenzene
              • NaCN, CuCN catalyst, warm
                • BENZONITRILE
            • undergoes A COUPLING REACTION *ACTING AS AN ELECTROPHILE. Phenol is dissolved in NaOH and added to the diazonium chloride solution in cold conditions (so overall cold alkaline conditions neccasery. HappenS. due to the positive charge carried by the diazonium ion - electrophiliically attacks phenols benzene ring (also works with aromatic amine. Just need the delocalised pi system of v high negative charge
              • TO FORM... diAZO-compounds, of two aromatic rings joined by a double bond between the two nitrogens(formely triple bond) VERY STABLE and unreactive. bright colours are the result of extensive delocalised electron systems spread across the entire molecule by the NN double bond coupling
          • ABOVE 5*c: PHENOL, NITROGEN AND WATER produced. (keep reaction vessel in ice water mixture) don't include hcl in eqaution
    • AMIDES
      • SYTHESIS
        • ACYL CHLORIDES. (Chlorine atom substituted for an  amine group be it NH2 if ammonia is added r else...)
          • Add  amine. Produces  a substituted amine. N - methyl indicates the sub allkyl group attached to the N (the alkyl group on the original added amine.
          • Add ammonia, no heating required.
            • FURTHER REACTION. Due to acid  HCL produced Reacting with the ammonia, to form ammonium chloride.
      • POLYMERIIZATION
        • ADDITION POLYMERISATION.
        • CONDENSATION POLYMERISATION . H2O by product in both cases
          • Requires  two types of molecule, with two of the same groups on their ends (that are different to eachother. One will contain a CO double bond, if not two.
            • Polyamides. Need diacyl chloride or dicarboxlyic acid, plus diamine (has two NH2 groups) . Forms AMIDE linkage with NH TO CO (double bond)
              • NYLON. Made up of two benzene derives monomers.
                • Synthetic FIBRE, when used in combo with other fibres adds to their durability. Ropes too used for as doesn't rot
              • KEVLAR.  Resists high temperatures, low thermal conductivity, high tensile strength, flame chemical and cut resistant
                • Sealants and adhesives
                • Data transmission cables, ropes
                • Bullet/stab proof vests
            • Polyesters. By diacyl chlorides, or  dicarboxlyic acids, or diacid anhydrides, plus a DIOL. Forms ESTER  Linkage, with CO double bond to an O atom.
              • Terylene. CLOTHING fabrics, hard wearing, easy to wash or dry
              • Plastic bottles
              • Polar fleece material
    • AMINO ACIDS. Contain amine group at one end, then a carbon with a H (can have an alkyl group on other bond), and carboxylic acid group at the other end. Name as amino then carboxylic acid name.
      • ZWITTERIONS.  Exists as an overal neutral ion in the solid state and neutral ph. Carboxylic OH loses the H, and NH2 gains an H.  Thus negative and positive charges form at either end dissolve in WATER ONLY. (As ionic and polar) .
        • IN ACID. Acts as a BASE. accepts H at nh2 and O-, so overall positive charge.
        • IN BASE. Acts as an ACID, donating a proton (technically two if changes from zwiterrion) with the COO- forming and NH2. Overall negative charge.
      • SEPERATION AND IDENTIFICATION BY CHROMATOGRAPHY.
        • ELECTROPHERESIS (for further separation. dependant on charge)
          • Spot seperated amino acid onto plate of special gel, electric current passed through it.
        • MAIN PROCESS s Do this after proteins have been hydrolysed. Put spot on bottom of paper, leave to dry, make into cylinder, fastening top with plastic clip
        • RETENTION  factoR: distance moved by áá divided by distance moved by solvent. Áás have different retention factors in different solvents.
        • EXTENSION: two way paper chromo : after main process, rotate paper 90*, then repeat main process with different solvent(like phenol and water)
      • AQUES' SOLUTIONS EFFECT ON PLANE OF PPLANE POLRISED MONOCHROMATIC LIGHT
        • All áás are optically active (save glycine as to hydrogens on central C atom.
        • All áás in living organisms are L ENANTIOMERS. lab scythed tend to be race,if mix.
      • PROTEIN FORMATION. When  amino acids undergo COMDENSATION POLYMERIStion With eachother, long chains of them are produced - linked by peptide bonds (actually AMIDE groups, but since many of them formed from amino acids, call them peptide bonds)
        • Hydrolysis of proteins. Reflux with dilute HCL, for up to 24 hours, then neutralise.
    • PARECETOMOL
      • 1. NITRATION of phenol, by NaNO3 and SULFURIC acid
        • 2.FRACTIONAL DISTILLATION. AS YOU Get isomers 2 and 4 nitrophenol (with higher boiling point due to more effective h bonding
          • 3. REDUCTION of the 4 nitroophenol to 4 aminophenol by NaBH4 in alkaline medium
            • 4. react with ETHANOYL CHLORIDE/ETHANOIC ANNHYDRIDE to give paractomol
    • NITRATION REACTIONS (adding NO2)
      • PHENOL
        • DILUTE NITRIC ACID alone, but produces 2, 4, 6 trinitrophenol, multiple substitions.
        • SULFURIC ACID AND SODIUM NITRATE (NaNO2) ONLY ONE SUBSTITUTION TAKES PLACE, TO THE 2 OR 4 POSITION.
      • BENZENE.  Add conch nitric and conc sulphuric acid, electrophilic substitution tak s place

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