Questions: Ordering Question Place the following groups in order of increasing leaving group ability. Place the worst leaving group at the top of the list. HS^- H3C^- HO^- HSe^-

Ordering Question
Place the following groups in order of increasing leaving group ability. Place the worst leaving group at the top of the list.
HS^-
H3C^-
HO^-
HSe^-

Transcript text: Ordering Question Place the following groups in order of increasing leaving group ability. Place the worst leaving group at the top of the list. $\mathrm{HS}^{-}$ $\mathrm{H}_{3} \mathrm{C}^{-}$ $\mathrm{HO}^{-}$ $\mathrm{HSe}^{-}$

Solution

Solution Steps

Step 1: Understanding Leaving Group Ability

Leaving group ability is determined by the stability of the group after it has left. A good leaving group is typically a weak base and can stabilize the negative charge well.

Step 2: Analyzing Each Group

$\mathrm{H}_{3}\mathrm{C}^{-}$: Methyl anion, very strong base, very poor leaving group.
$\mathrm{HO}^{-}$: Hydroxide ion, strong base, poor leaving group.
$\mathrm{HS}^{-}$: Hydrogen sulfide ion, weaker base than hydroxide, better leaving group.
$\mathrm{HSe}^{-}$: Hydrogen selenide ion, even weaker base than $\mathrm{HS}^{-}$, best leaving group among the given options.

Step 3: Ordering the Groups

Based on the analysis, the order from worst to best leaving group is: