Reaction with Grignard and organolithium reagents

Table 17.2 summarizes the reactions of aldehydes and ketones that you ve seen in earlier chapters. All are valuable tools to the synthetic chemist. Carbonyl groups provide access to hydrocarbons by Clemmensen or Wolff-Kishner reduction (Section 12.8), to alcohols by reduction (Section 15.2) or by reaction with Grignard or organolithium reagents (Sections 14.6 and 14.7). 

Mechanism 14-4 Base-Catalyzed Opening of Epoxides 653 14-14 Orientation of Epoxide Ring Opening 654 14-15 Reactions of Epoxides with Grignard and Organolithium Reagents 656 14-16 Epoxy Resins The Advent of Modern Glues 656 Summary Reactions of Epoxides 658 EssentialTerms 660 Study Problems 662... 

Reactions of Epoxides with Grignard and Organolithium Reagents... 

The enhanced reactivity of allylic halides and tosylates makes them particularly attractive as electrophiles for Sn2 reactions. Allylic halides are so reactive that they couple with Grignard and organolithium reagents, a reaction that does not work well with unactivated halides. 

The addition reactions of Grignard and organolithium reagents with carbonyl groups and carboxylic acid derivatives are summarized in Table 3.2. 

The reactions of Grignard and organolithium reagents, especially with pyridazine derivatives, was discussed in CHEC-I <84CHEC-i(3B)i>. Pyridazine derivatives tend to undergo addition to C-... 

A. Rosenthal and S. N. Mikhailov, Branched-chain sugars. Modifications in the reaction of l,2 5,6-di-0-isopropylidene-a-DTribo-hexofuranos-3-ulose with Grignard and organolithium reagents, J. Carbohydr. Nucleosides Nucleotides 6 237 (1979). 

The one-pot reaction of N-methoxy-N-methyl-2-pyridyl urethane 1292 with Grignard and organolithium reagents provides an efficient method for the preparation of unsymmetrical ketones 1294 [963]. 

Reaction of Grignard and organolithium reagents with aldehydes and ketones (Section 14.5) A method that allows for alcohol preparation with formation of new carbon-carbon bonds. Primary, secondary, and tertiary alcohols are all accessible. 

We saw an example of nucleophilic ring opening of epoxides in Section 15.4, where the reaction of Grignard and organolithium reagents with ethylene oxide was presented as a synthetic route to primary alcohols ... 

Preparation of 2-substituted a-Alkenes. The reaction of trimethylsilylacetone with Grignard and organolithium reagents has been employed in the synthesis of 2-substituted propenes via the formation of a /3-hydroxysilane, which is then subjected to a Peterson elimination (eq 1). It was also used to prepare, y-unsaturated esters, nitriles, and amides (eq 2). ... 

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