Consider thiol anion `(RS^(Theta))` and alkoxy anion `(RO^(Theta))`. Which of the following statement is correct?

Options

A. `RS^(Theta)` is less basic and less nucleophilic than `RO^(Theta)`
B. `RS^(Theta)` is less basic but more nucleophilic than `RO^(Theta)`
C. `RS^(Theta)` is more basic and more nucleophilic than ` RO^(Theta)`
D. `RS^(Theta)` is more basic but less nucleophilic than `RO^(Theta)`

Answer

B

Explanation

Since O-H bond is stronger than S-H bond, `RO^(-)`has greater tendency to accept a proton than `RS^(-)` and hence RO is a stronger base than `RS^(-)`. Conversely, since Sis less electronegative than O, RS-has greater tendency to donate a pair of electrons than `RO^(-)` and hence `RS^(-)`is more nucleophilic than RO.