CHEM 203 Lecture Notes - Lecture 29: Grignard Reaction, Vinyl Chloride, Organochloride
Document Summary
Mgcl note: vinyl and aryl halides do undergo elimination and substitution reactions. This chemistry, however, is beyond the scope of chem 203. Lack of reactivity of vinyl and aryl halides in substitution reactions of the sn2 and sn1 type for reasons that will be illustrated in chem 213. Incompatibility of grignard / organo-li reagents with: bronsted acidic groups (pka less than ca. 40) present on the same molecule, e. g. h o pka 18 boldface h"s will protonate grignard / organo-li species. Topics discussed on nov. 10: electrophilic groups present on the same molecule, e. g. electrophilic: the grignard rgt. would add to the c=o. Br: potential leaving groups present at the -position, e. g. lecture of nov 10 p. 2. Ch2=ch2 + br + mgbr pka 8. Ch2=ch2 + och3 + mgbr pka 17. G << 0 therefore, the above alkyl halides fail to yield stable grignard or organolithium reagents.
