Soluções de Problemas Químicos

Prévia do material em texto

Solutions to Problems . 287 Water can similarly add to the other end of the allylic the other position with positive charge. and again to either face of the ring. relative to the ethyl group: CH₃ CH₃ H H + CH₃ H H H H H + H₂O: H CH₃ CH₃ H H H H + H H H Thus, in all, four isomeric products are possible. MgCl D MgCl D-OD D-OD 43. and D CH₃ CH₃ CH₃ CH₃ OH 44. Li CH₃ C CH₃ 1. THF TMEDA 2.H⁺,H₂O THF or Br NBS. Li. hv. THF (Grignard reagent is also okay.) 45. (a) or (2E, 5Z)-2.5-heptadiene (b) (c) (5S, 6S)-5,6-Dibromo-1,3-cyclooctadiene (d) 4-Ethenylcyclohexene H 46. 1,4-Pentadiene has the weakest C-H bond (arrow). a bond that is doubly allylic ~ 77 kcal this isomer will therefore be brominated fastest. Because only a very