Addition of Grignard reagents and organolithiums

Addition of Grignard reagents and organolithium compounds (Sections 14 6-14 7) Aldehydes are converted to secondary alcohols and ketones to tertiary alcohols... 

Addition of Grignard reagents and organolithium compounds to the pyridazine ring proceeds as a nucleophilic attack at one of the electron-deficient positions to give initially... 

The Addition of Grignard Reagents and Organolithium Reagents to Aldehydes and Ketones... 

The most important synthetic use of Grignard reagents and organolithium reagents is to form new carbon-carbon bonds by addition to polar multiple bonds, particularly carbonyl bonds. An example is the addition of methyl-magnesium iodide to methanal ... 

The addition of Grignard reagents or organolithiums (alkenyl, alkyl, alkynyl, allyl or aryl) to nitroenamines (281)213 was reported by Severin to afford P-substituted-a-nitroalkenes.214 b Similarly, ketone enolates (sodium or potassium), ester enolates (lithium) and lactone enolates (lithium) react to afford acr-nitroethylidene salts (294) which, on hydrolysis with either silica gel or dilute acid, afford 7-keto-a,(3-unsaturated esters or ketones (295)2l4c-d or acylidene lactones (296).214 Alternatively, the salts (294, X s CH2) can be converted to -y-ketoketones (297) with ascorbic acid and copper catalyst. 

The addition of Grignard reagents2108 and organolithium2l0b to enaminones (279) is an efficient process for the synthesis of a, 3-unsaturated esters and ot, 3-enones. Typically, the enaminones are obtained by the treatment of activated methylene or methyl groups with dialkylformamide dialkyl acetals.211 A variety of organolithiums have been added to enaminones, while Grignard reagents have been utilized... 

The mechanism of 1,2-nucleophilic addition is the same as already described. It is found that Grignard reagents and organolithium reagents will react with a,p-unsaturated aldehydes and ketones in this way and do not attack the p-position ... 

In addition, Figures 10.27,10.32 and 10.46 present the current view on (1) the mechanisms of the addition of Grignard reagents to carbonyl compounds, (2) the mechanism of the additions of organolithium compounds to ,/i-unsaturated ketones and (3) the mechanism of the 1,4-addition of Gilman cuprates to ce,/J-unsaturated ketones, respectively. 

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