H C Nuc CH 2 R' R H C LG R'H 2 C R CH 2 R' C LG H R C C H R H C Nuc CH 2 R' R H C Nuc R'H 2 C R H C C H R H R' LG C C R H R' H Ch. 7 ----- SN1, SN2, E1, E2 Nolta 2006 Nuc + LG SN2 or Bimolecular Substitution Electrophilic sp3 carbon (due to LG taking electrons One-sided attack leads to inversion at C-chirality maintained One step slow step C C Nuc: R H R' H + Racemization C+ intermediate-loss of chirality in mix Base E2 or "Anti" elimination - FIND ALL POSSIBLE β Cs with Hs: The LG and the H removed from the adjacent C must be in the s a m e p l a n e in order for the p orbitals to align, hence the "anti" conformation leads to the fastest E2. This alignment determines the configuration of the double bond that forms; if more than one H is available on a b C, both double bond stereochemistries are possible (trans is always preferred) if more than one C has an available H the more substituted double bond will form first (i.e. take the H from the most substituted adjacent C first)
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