snrxns - > Cl-Leaving Groups Favored by better leaving...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Summary of Nucelophilic Substitution Reactions S N 1 S N 2 Mechanism Two Steps R L R + Nu: R Nu One Step R L + Nu: R Nu Kinetics 1st order (unimolecular) rate= k[R-L] Ionization= rate determining step (1st step), 2nd step does not effect the rate 2nd Order (bimolecular) rate= k[R-L] [Nu:] Stereochemistry Racemization Inversion Carbon (sp 3 ) Electrophile Favored by electrophiles which can best stabilize a carbocation. 3°> benzylic ~ allylic ~ 2°>> 1° Steric hinderance controlled CH 3 > 1°> 2 (3°= no reaction) Nucleophile Nature of the nucleophile has no effect on rate Favored by better nucleophiles RS - > NC - > I - > RO - > HO
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: -> Cl-Leaving Groups Favored by better leaving groups-N 2 > -OTos > -I > -Br > -Cl >-OH 2 Favored by better leaving groups-N 2 > -OTos > -I >- Br > -Cl > Solvent Effect Favored by polar, ionizing solvents. Solvolysis: polar protic (H-bonding) solvents act as the nucleophile H 2 O > H 2 O/ROH (mixed solvent) > ROH Favored by polar aprotic solvents. HMPA > CH 3 CN > DMF > DMSO > THF Disfavored by polar protic (H-bonding) solvents Competative Reactions Elimination (E1) Rearrangements Elimination (E2) by strongly basic nucleophiles...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online