NUCLEOPHILE ASSIGNMENT Name: ………………………………

For each of the following nucleophiles, write its formula, name and pKb, in the correct column.

HSO4-, H2PO4-, CH3COOH (pKb 21), ROH, H2O, NO3-, F-, Cl-, CH3COO-, NH3, RNH2 (amine, pKb ca. 4), N3- (azide), Br-, OH-, RO-, CN- HS- (hydrosulfide), RS- (alkyl sulfide), NH2-, I-, H-, and R-CºC-

Use the tables in your test aids

q  Obtain Nu:- strength from the table entitled “Strength of Nucleophiles (Nucleophilicity)’ on page 3.

q  Obtain pKb values from the tables entitled ‘Strength of Acids and Bases’ (page 1) and Approx. pK Values (page 2)

q  Use the following scale of pK values to classify the strength of the base.

Strength / strong / moderate / weak / neutral
pK / £1 / 2 - 8 / 9 - 12 / ³ 12
Substrate / neutral
fair to good Nu / strong base
good Nu / moderate to weak base
good Nu / moderate to weak base
fair Nu / neutral
weak Nu
Me° / SN2 / SN2 / SN2 / SN2 / no reaction
1° / SN2 / SN2 / SN2 / SN2 / no reaction
2° / SN2 / E2 / SN2 (less E2) / E2, (less SN2) / SN1, E1
3° / SN1 / E2 / E2 / E2 / SN1, E1
I-, iodide 23 / OH-, hydroxide -1.74 / CN-, cyanide 4.7 / CH3COO-, acetate 9.3 / H2O, water 15.74


Predict the reaction mechanism for the substrate with each of the nucleophiles shown.

NaOH / KCN / CH3COO- Na+ / H2O / LiI
Me° / CH3Br / SN2
NaHS / (CH3)3CO-Na+ / NaF / CH3COOH / NaH
CH3CH2Br
NaN3 / CH3CºC- Na+ / CH3CH2OH / KCl / NH3
(CH3)2CHBr
LiCl / CH3CH2O- Na+ / CH3NH2 / NaNO3 / NaHSO4-
(CH3)3CBr
KOH / NaCl
CH2=CHBr
NaH / KI
C6H5Br


Draw the major products for the substrate reacting with each of the nucleophiles shown.

CH3Br
(Me°) / NaOH / KCN / CH3COO- Na+ / H2O / LiI
SN2
CH3OH + NaBr
CH3CH2Br / NaHS / (CH3)3CO-Na+ / NaF / CH3COOH / NaH
(CH3)2CHBr / NaN3 / CH3CºC- Na+ / CH3CH2OH / KCl / NH3
(CH3)3CBr / LiCl / CH3CH2O- Na+ / CH3NH2 / NaNO3 / NaHSO4-

Nucleophile Assignment Page 1 of 3