Complete the following and state the relations between configurations of the reactant and products.
(i) `._(D-)MeCH(OH)Et + Ac_2 O rarr` ?
(ii) `._(D-)MeCH(Cl)COOH + 2 NaOH rarr` ?

Explanation

If no bond to the asymmetric C atom is broken, no inversion takes place. If it breaks then for `SN^2` reaction inversion takes place , and for `SN^1`, retention and racemisation take place.

(ii) Depending on the conditions, it can be `SN^2` or `SN^1`, If the concentration of base is high. `SN^2` mechanism occurs and hence inversion takes place.

If the case is dilute, `SN^1` mechanism occurs, therefore, retention and racemisation are expected , but neighbouring group participation of `(COO^(Ө))` operates.

Due to the 'protection', the `overset (Ө) O H` ion attracks from the same side and hence retention occurs.