Grignard reagents aldehyde reactions with

Osmium tetroxide, reaction with alkenes, 235-236 toxicity of, 235 Oxalic add, structure of, 753 Oxaloacetic acid, structure of, 753 Oxetane, reaction with Grignard reagents, 680 Oxidation, 233, 348 alcohols, 623-626 aldehydes, 700-701 aldoses, 992-994 alkenes, 233-236 biological, 625-626 phenols, 631 sulfides, 670 thiols, 668... 

It should be noted that, on reaction with Grignard reagents, aldehydes will produce secondary alcohols, whereas ketones will form tertiary alcohols. Often forgotten is the possibility of synthesizing primary alcohols by using formaldehyde as the substrate. 

Complicated aldehydes and ketones are made by oxidizing complicated alcohols, By reaction with Grignard reagents these aldehydes and ketones can be converted into even more complicated alcohols, and so on. 

Reaction with Grignard reagents. Edwards and Kammann7 studied the reaction of phenylmagnesium bromide in ether at —70° with one equivalent of formic-acetic anhydride and found that the less hindered carbonyl group of the mixed anhydride reacts preferentially, with the result that the aldehydic product (5) predominates strongly over the methyl ketone (6). With ether as solvent, the ratio... 

Methoxyamine solid supports 7x can be used to anchor carboxylic acids in the presence of BOP/DIEA as Weinreb amides [338,339]. The resultant anchor is compatible with peptide assembly using Boc or Fmoc strategies, and treatment of the final sequence with LiAlH4 in THF led to release of peptide aldehydes. A related support with RAM as the base resin has also been used to prepare resin-bound Weinreb amides, which afforded ketones on cleavage induced by reaction with Grignard reagents [340]. 

The answer is B. Aldehydes can undergo nucleophilic addition reaction with Grignard reagents. The major product here is 3-pentanol which is a five carbon alcohol. 

Stereoselective alkene synthesis starts from the reaction of triethylsilyloxirane 117 with an organocuprate reagent and is concluded by oxidation of the formed P-silyl alcohol to the aldehyde, whose reaction with Grignard reagent and elimination of [EtjSi/OH] leads to either the ( )- or the (Z)-alkene (118 or 119) by using different reagents (Schane 7.45). 

Consequently, aldehydes and ketones undergo nucleophilic addition reactions with Grignard reagents (Section 17.3). 

Alcohol synthesis via the reaction of Grignard reagents with carbonyl com pounds (Section 14 6) This is one of the most useful reactions in synthetic organ ic chemistry Grignard reagents react with formaldehyde to yield primary alco hols with aldehydes to give secondary alcohols and with ketones to form terti ary alcohols... 

Reaction of Grignard reagents with aldehydes and ketones (Section 14 6)... 

Table 17 2 summarizes the reactions of aldehydes and ketones that you ve seen m ear her 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 organolithmm reagents (Sections 14 6 and 14 7)... 

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