Question

24. In which of the following reaction pair of diastereomers will form ?
OH
(2) LOH
(b) >
>
(d) All of these
OH​

Answer 1

Answer:

I am aware of the fact that HBrHBr gives anti addition product and BH3BHX3 forms syn addition product. In part (a) since the back side is less sterically hindered ( due to presence of only HH ) BR−BRX− preferentially attacks from the back side.Similar is the case with (b).c) proceeds with a free radical mechanism.d) however occurs via anti-markinicoff addition so that OHOH adds to the primary carbon.Since there are two possible ways in which the OHOH group may add( either from the back side or the front side)my idea is that it may result in a pair of diastereomers. However I am not quite sure about it. Thanks.