SN1 vs SN2 and Alkyne Reactions Review

Flashcards covering the comparison between SN1 and SN2 reaction mechanisms and common alkyne reagents as outlined in the lecture notes.

SN1 Steps

Multiple

SN1 Intermediate

Carbocation

SN1 Rate Law

$$k[RX]$$

SN1 Best substrate

$$3^\circ$$

SN1 Nucleophile

Can be weak

SN1 Preferred solvent

Polar protic

SN1 Stereochemistry

Racemization

SN1 Rearrangements

Possible

SN1 Energy diagram

Usually two humps

SN2 Steps

One

SN2 Intermediate

None

SN2 Rate Law

$$k[RX][Nu]$$

SN2 Best substrate

Methyl or $1^\circ$

SN2 Nucleophile

Usually strong

SN2 Preferred solvent

Polar aprotic

SN2 Stereochemistry

Inversion

SN2 Rearrangements

Not possible

SN2 Energy diagram

One hump

$H_2/Pd-C$ (with alkyne)

Yields an alkane

$$H_2/Lindlar$$

Yields a $cis$ alkene

$$Na/NH_3(l)$$

Yields a $trans$ alkene

$$HgSO_4 / H_2SO_4 / H_2O$$

Alkyne reaction resulting in a ketone

$$9\text{-BBN}; H_2O_2/OH^-$$

Yields an aldehyde from a terminal alkyne

$$NaNH_2$$

Used to deprotonate terminal alkyne or perform elimination

acetylide $1^\circ RX$

Creates a new $C-C$ bond