...chapter 10 conjugation in alkadienes and allylic systems...
§10.11 Addition of Hydrogen Halides to Conjugated Dienes Example: HCl Example: via: H X Protonation of the end of the diene unit gives an allylic carbocation. and: 3-Chlorocyclopentene 1,2-addition of XY 1,2-Addition versus 1,4-Addition ...