Question

Q4a - The reaction of butan-2-ol with concentrated aqueous HBr goes with partial racemization, giving more inversion than retention of configuration. Propose a mechanism that accounts for partial inversion. Draw all the arrows to indicate movement of electrons, write all lone pairs involved into electron transfer, all formal charges, and all the products for each step. If a racemic mixture is formed, you may indicate this using a wavy line www or mark the chiral center with an asterisk (*), and write racemic in the box. In the dotted box write the mechanistic element for each transformation (i.e. protonation, deprotonation, Nu attack, loss of leaving group). Full credit will also be given if the mechanism is fully completed in a free format, which follows the above instructions. OH H-Br: partially inverted product 94b - Write the full name and/or the common abbreviation of the mechanism above. Q4c - In a few words explain why complete racemization does NOT occur.

Answer 1

I Retention . Inversion The inverted product is formed in larger amount because the attack of be on that side from where H2O is leaving is slightly difficult