14.7 Synthesis of Alcohols Using Organolithium Reagents TABLE 14.3 Reactions of Grignard Reagents with Aldehydes and Ketones General equation and specific example Reaction with formaldehyde H Grignard reagents react with formal diethyl dehyde(CH2=o) to give primary alcohols having one more carbol than the Grignard reagent. Grignard Formaldehyde reagent HOH HCH diethyl ethe Cyclohexylmagnesium chloride (64-69% Reaction with aldehydes Grignard (RCH=O)to give secondary alcohols. RMgx Grignard Aldehyde Secondary Secondary alkoxymagnesium CH3 (CH 2)4CH2MgBr CH3 CH 1. diethyl ethe CH3(CH2)4CH2 CHCH3 HexyImagnesium Ethanal 2-Octanol (84%) Reaction with ketones Grignard diethyl RMgX R'CR OMaX reagents react with ketones(RCr) to give tertiary alcohols Grignard Ketone ertiary alkoxymagnesiun alcohol CHaMgCI 1. diethyl eth 2.H2O H3C Methylmagnesium Cyclopentanone 1-Methylcyclopentanol chloride Back Forward Main MenuToc Study Guide ToC Student o MHHE Website14.7 Synthesis of Alcohols Using Organolithium Reagents 555 TABLE 14.3 Reactions of Grignard Reagents with Aldehydes and Ketones Reaction Reaction with formaldehyde Grignard reagents react with formal￾dehyde (CH2œO) to give primary alcohols having one more carbon than the Grignard reagent. Reaction with aldehydes Grignard reagents react with aldehydes (RCHœO) to give secondary alcohols. Reaction with ketones Grignard reagents react with ketones (RCR) to give tertiary alcohols. O X General equation and specific example RMgX Grignard reagent Formaldehyde HCH O diethyl ether H3O OMgX H R C H Primary alkoxymagnesium halide OH H R C H Primary alcohol RMgX Grignard reagent Aldehyde RCH O diethyl ether H3O OMgX H R C R Secondary alkoxymagnesium halide OH H R C R Secondary alcohol RMgX Grignard reagent Ketone RCR O diethyl ether H3O R C OMgX R R Tertiary alkoxymagnesium halide R C OH R R Tertiary alcohol MgCl Cyclohexylmagnesium chloride CH2OH Cyclohexylmethanol (64–69%) Formaldehyde HCH O 1. diethyl ether 2. H3O CH3(CH2)4CH2MgBr Hexylmagnesium bromide Ethanal (acetaldehyde) CH3CH O 2-Octanol (84%) CH3(CH2)4CH2CHCH3 OH 1. diethyl ether 2. H3O CH3MgCl Methylmagnesium chloride O Cyclopentanone 1-Methylcyclopentanol (62%) H3C OH 1. diethyl ether 2. H3O Back Forward Main Menu TOC Study Guide TOC Student OLC MHHE Website