Grignard reagents carbonyl compound reactions

The mam synthetic application of Grignard reagents is their reaction with certain carbonyl containing compounds to produce alcohols Carbon-carbon bond formation is rapid and exothermic when a Grignard reagent reacts with an aldehyde or ketone... 

CARBONYL ADDITIONS, CERIUM(III) CHLORIDE-PROMOTED, 76, 237 Carbonyl compounds, reactions with organolithiums or Grignard reagents, 76, 228 Carboxylic acid amides, 77, 27 Cells, storage of, 76, 80 Centrifugation, 76, 78... 

Treatment of bromocyclopropane with magnesium to form the corresponding Grignard reagent and subsquent reaction with a carbonyl compound gave cyclopropylmethanols 4 in poor to good yield. " ... 

Association between RMgX and Carbonyl Compounds Reactions of Benzophenone(s) with Grignard Reagents... 

Reaction of an ester with a Grignard reagent involves the alcohol containing the two identical alkyl groups from the formation of two successive tetrahedral carbonyl addi- Grignard reagent, tion compounds. The result of the overall reaction is an... 

The use of organocadmium compounds, RjCd, lies in the fact that they react only with acid chlorides and no other carbonyl compounds. Thus, acid chlorides can be converted to ketones with no risk of further reaction. Organocadmium compounds are prepared (Equation 15.3) by reaction of cadmium chloride with a Grignard reagent, and the reactions only work well when R is aryl or primary alkyl. An example is provided in Figure 15.45. 

The anion B is just the enolate anion of a carbonyl compound, actually the same as A. So there is no need to use a Grignard reagent or any other synthetic equivalent in this reaction anion B itself can be the intermediate and we simply treat the aldehyde with mild base ... 

In equation 1, the Grignard reagent, C H MgBr, plays a dual role as reducing agent and the source of the arene compound (see Grignard reaction). The Cr(CO)g is recovered from an apparent phenyl chromium intermediate by the addition of water (19,20). Other routes to chromium hexacarbonyl are possible, and an excellent summary of chromium carbonyl and derivatives can be found in reference 2. The only access to the less stable Cr(—II) and Cr(—I) oxidation states is by reduction of Cr(CO)g. 

The reaction involves nucleophilic substitution of for OR and addition of R MgX to the carbonyl group. With 1,4-dimagnesium compounds, esters are converted to cyclopentanols (40). Lactones react with Grignard reagents and give diols as products. 

Alcohol synthesis via the reaction of Grignard reagents with carbonyl compounds (Section 14.6) This is one of the... 

Grignard reagents that contain a /3-hydrogen—e.g. 15—can reduce a carbonyl substrate by transfer of that hydrogen as a side-reaction. The so-called Grignard reduction is likely to proceed via a six-membered cyclic transition state 16 the alkyl group of alkylmagnesium compound 15 is thereby converted into an alkene 17. 

Alcohols from Reaction of Carbonyl Compounds with Grignard Reagents 613... 

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