Rules of the Day 2-6-09 1 . Organolithium reagents are extremely basic, in fact some of the strongest bases known . You must always worry about competing deprotonation when using an organolithium reagent. 2. Grignard reagents are also strong bases, but not as strong. They will deprotonate any species that is equal to or more acidic than an alcohol (pKa = 16 or lower). 3. Organilithium and Grignard reagents are very useful because they react as nucleophiles with epoxides at the less hindered site to give new carbon-carbon bonds ! 4. Gilman reagents (R 2 CuLi) are formed from reaction of 2 equivalents of organolithium reagents with 1 equivalent of CuI. Once again, there is a partial negative charge on the carbon atom attached to the metal atom. 5. Gilman reagents are very useful because they react as nucleophiles with primary alkyl halides, vinylic alkyl halides (halogen atom attached to sp2 carbon of a double bond) and epoxides at the less hindered site to give new carbon-carbon bonds ! 6.
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