CH 231 Lecture Notes - Lecture 11: Substitution Reaction, Leaving Group, Alkane

• School: University of Alabama
• Department: Chemistry
• Course: CH 231
• Professor: timothysnowden

Document Summary

Chapter 8 continued: 8. 4 preparation of haloalkanes, recall, haloalkanes can be prepared by radical reactions with alkanes and some alkenes. Ch 231-001 week 11 notes: regioselectivity trends in radical halogenations, reactions occur through radical intermediates, as electron-deficient species, radicals are stabilized much like carbocations, through resonance delocalization and induction. Ch 231-001 week 11 notes: note: radical halogenation cannot occur at the second carbon of a non- conjugated allylic system. Ch 231-001 week 11 notes: radical autooxidation, triplet oxygen a low-reactivity, destructive diradical. Ch 231-001 week 11 notes: consumed antioxidants: oxygen (radical) scavengers. Most possess allylic c-h, benzylic c-h, or phoh groups that can form relatively stable resonance delocalized radicals: 8. 8 radical addition of hbr to alkenes (non-markovnikov, reaction fails with hcl and hi. That is, the electrophilic carbon must be sterically accessible (unhindered: the substrate must possess a good leaving group, sn1 substitution nucleophilic unimolecular.