Organic Chemistry Reaction Things

SN1

prefers 2° and 3° leaving groups (or 1° with resonance)

SN1

Rate = k[E+], is unimolecular

SN1

reacts with weak/neutral nucleophile

SN2

Prefers 1° and 2° leaving groups

SN2

needs good/strong/anionic (-) nucleophile

Strong

I -

Strong

HS -

Strong

HO -

Strong

Br -

strong

H₂S

strong

RO -

strong

Cl -

strong

RSH

Strong

N≡C - 

Weak

F -

weak 

H₂O

Weak

ROH

conjugate of a strong acid

Stable leaving groups are the _______________________

Sn² (Good nuc-, no base)

-CN, -N3, -SR,SeR, R3P, R3N, R2Se

primary & secondary

Not Practical for Sn²

-CN, -N3, -SR,SeR, R3P, R3N, R2Se

Tertiary

Sn2 major + E2

(Strong NUC-/ Strong Base BUT bulky favors E2)

HO-, RO-, H2N-, R2N-

Primary

E2 major + Sn2

(Strong NUC-/ Strong Base)

HO-, RO-, H2N-, R2N-

Secondary

E2 only

(Strong NUC-/ Strong Base)

HO-, RO-, H2N-, R2N-

Tertiary

E2

(Base ONLY, must have beta H, bulky)

C9H16N2, C7H12N2

Primary, secondary, tertiary

Not Practical

(Primary Carbocation is too high in energy)

H2O, CH3OH, CH3CH2OH

Primary

Sn1 major, E1

(neutral O are weak nuc-/base)

H2O, CH3OH, CH3CH2OH

Secondary, Tertiary

Low Temp

E1 major, Sn1

(neutral O are weak nuc-/base)

H2O, CH3OH, CH3CH2OH

Secondary, Tertiary

High Temp

SN1 like (weak nuc- attacks carbocation)

Epoxide in acidic soln

SN2 like (strong nuc- attacks)

Epoxide in acidic soln

Becomes aldehyde

Primary alcohol w/ CrO3, H2SO4