Zadanie 8e
Wzorowane na: Chemistry HL Paper 2, May 2022, TZ2, pytanie 8(e). Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Informacja do zadań 8a-8f.
Carbon occurs as several allotropes and forms an enormous variety of organic compounds.
Polecenie
(i) Explain the mechanism of the reaction between 1-chloropropane, CH3CH2CH2Cl, and aqueous potassium hydroxide, KOH(aq), using curly arrows to represent the movement of electron pairs.
(ii) Deduce the splitting pattern, in the NMR spectrum of 1-chloropropane, of the signal of the CH3 protons and of the signal of the CH2 protons bonded to the chlorine atom.
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
(i) curved arrow from the lone pair / negative charge on the O atom of HO− to the carbon atom bonded to Cl ✔
curved arrow showing the C–Cl bond breaking «from the bond to the Cl atom, in the reactant or in the transition state» ✔
transition state showing the negative charge, square brackets and partial bonds between C and both O and Cl ✔
products CH3CH2CH2OH AND Cl− ✔
(ii) CH3: triplet AND CH2Cl: triplet «each is next to a CH2 group» ✔
Schemat punktowania
(i) [1] each as shown. Do not accept an arrow starting at the H atom of HO−. Do not penalize if O and Cl are not drawn at 180° in the transition state. Award [3 max] for a correct SN1 mechanism (carbocation). (ii) both patterns are needed for the mark.