Nucleophilic Substitution 5N1 and 5N2 Summary Questions t Isa nucleophile? Give some examples of nucleophiles‘. 4 CHéNilCG/JPGCH’J I ' m ; ddhétkf 0W éié'C/Tc’h [ M i r (UW‘S ““69 Maui} 196MB IL 01‘]: Why CN: 0 “W30 [441,54 h a v e , ([sz [420 do nucleophiles attack the carbonhalogen bond of a halogenoadane? C ““X ; E 3 {N*M‑ 7‘0 r [Iwgrfdtl‘i’fi +he Carbd’h :5 (£55 eacr’rme ‘afwe fl m m fi v e halo, 6mh 4m: :5 Parfiall posh’vt’e. The. fioc‘gofln/e Is éuch/"c a(fnac/ed fa flm/ C SIM“; What is the genera! equation for the reaction of a halogenoalkane and a strong ba £ v a + :01!“ K~OH -‐9 ‘i X“ Write the general equation for Nucleophilic Substitution (showing the nucleophile and Halogen (X)) ,, V. R‘X + ? c h R‘NLL 4 X ’7‘ What'Is heterolytic fission? 6L0‘ band fuming #3le . euchwsj‘l ~ 67» 63+176 671( ~9 5r min”; 5591-7 36F SN , tep, 1 (prImary)... In the dIagrams below, show the m o v e m e n t of the electron pairs with the curly arrow... Nucleophile attacking Unstable transition state (with Formation of alcohol and the release of halogenoalkane from the back nucleophile and halogen both the leaving group (halide) attached by weak bonds)... Show the charge on the molecule". G) - Na: \ n ®0‐X ‘2 V l) I [1 Nu~~-cw-X' (39 “ Nu. ‐ . w" J.) : i/ r Why (tees the 5N2 mechanism favour primary halogenoalkanes and n o t tertiary? (Think There ("5‘ I‘I’I‘I’Ie Jieric hiflfilmnw . / 6) c. 5° *4"? X a‘hout‘steric hin‘dran-Ce),v '55 ” W m Explain why the SN2 mechanism is bimoiecuiar Write the rate equation for this mechanism hulw‘lkawé “4 7“”: ’ml"* NH IIbC/€ (7l’?/II/t‘ IIIIISI‘ (OIIIC/t’ LHIL“ “HIE ral‐e dekImII/IIIIg-S‘KP) kaQO][RX7 0 What happens to the arrangement of the a t o m s around the carbon a t o m after 5N2? IIIveIcsicWL 0% Hie ISRI”IOCII~I{-CI" (20.3) 5N1, 2 Step, 3° (tertiary)... in the diagrams below, show the m o v e m e n t of the electron pairs with the curly arrow... Step 1: Heterolytic fission of the carbon‐haiogen bond Step 2: Carbocation intermediate attacked by nucleophiie (ionizes the halogenoaikane). leading to n e w bond... Halide ion will leave, producing a carbocation intermediate. ' The presence of 3 alkyi groups on the tertiary haiogenoalkane has what effect on the carbocation? s'mbI-IIze e» {(4. Thea 4116 C a m e cah 6K V14 HM Foul? V6 Mow W N Explain why the 5N1 mechanism is unimoiecuiarI Wr i t e the r a t e equation for this mechanism. Tm FmS’I‘ 25R]? i5" We 3"“? ” ( P 0 ” “ Io I [M5 “fly 6716’ I [III Which nucleophilic substitution mechanism do 2° (secohdary) haldgenoalkanes undergo? 80W! Factors t h a t affeCt the rate of nuci’eOphii What are the three factors that affect the r a t e of nucleophiiic substitution? i/iflllde‘ .. RIIIpeIafure. 5:33:20 m Ii " L x7 7 ‘* ?fré’wjf’h (5} defop/III/t HI readoun‘ ‘ ’ Give the order of rates according to the type of halogenoalkanei Start with the fastesthalogenoatkane and annotate which SNmechanism is applicable under each halogenoalkanei 5A,] Huffy“ Him) K‘I > R-Br > . gm)‑ K‘Ci > R~F Explain how the influence of the leaving group involves: (a) polarity of the carbon‐halogen bond Mora (leth’oMEjaHve.3l”ovP 5mm; M ( ‘ N N ‘ F S flu”: IMMUQJ Bur vp reaction (b) strength of the carbon-halogen bond flnalifle halt:K +11% em M é i L C j (L 5/15” 1"!“ [957/163 (SIGIWLH reach0% Describe which (polarity or strength) of the carbon-haiogen bond is the dominant factor for determining rate. L9h’Ql/tflflt is (mpfltflnt [more Explain which solvents (polar & protic/polar & aprotic) are favoured by: Profit 5N11 Palm“, 5N2: [00(th “P'v/H , '- S‘ffltailllé'ej CaxrmCat/‘iflk IWRD'VW-Edlfll‘fi does (”of SLHL'LHCl Moe i'wCHOP‘II/f’, $clvmt M H r a H - w ‘ n j (4665 ncf‘isiow 17‘ d o w n (~ch 9M3): (5,0 ’Ihierfasrtest [reactions will, be tertiary iodoailvkgnesjn polar,feroticfisolvenrti’ Explain the statement above using understanding about: ' ' ° ' 9 10, 20 and 30halogenoalkanes [0 : SN 2 I 5 “WV 3 ; the mechanisms they favour which is the best carbon~halogen bond (in t e r m s of rate) C“ 1: we the Choice of solvent that each mechanism favours J . . peim/ [profit b n o n ittbill'ze, We w J _‘ a 5N1 ) {6151‘ 01116 5% b '3)? (1 (Vil‐iimf 61167”; Q