Ketone-aldehydes => alkyl halides

Dipotassium iron tetracartionyl in the synthesis ol aldehydes and ketones (tom alkyl halides. 

Dialkyl cuprates may also be added to aryl vinyl sulphoxides and the resulting a-sulphinyl carbanions can be treated with various electrophiles such as aldehydes, ketones and alkyl halides (equation 350)643. 

Aldehydes or ketones and Alkyl halide and silver salts of ... 

The definition of what constitutes reactive or unstable functionality naturally varies somewhat, but there is also a good deal of consensus (aldehydes, alkyl halides, vinyl ketones, and so forth) [14,16-18]. 

The metalation of vinyl ethers, the reaction of a-lithiated vinyl ethers obtained thereby with electrophiles and the subsequent hydrolysis represent a simple and efficient method for carbonyl umpolung. Thus, lithiated methyl vinyl ether 56 and ethyl vinyl ether 54, available by deprotonation with t- or n-butyllithium, readily react with aldehydes, ketones and alkyl halides. When the enol ether moiety of the adducts formed in this way is submitted to an acid hydrolysis, methyl ketones are obtained as shown in equations 72 and 73 . Thus, the lithiated ethers 56 and 54 function as an acetaldehyde d synthon 177. The reactivity of a-metalated vinyl ethers has been reviewed recently . 

Predict the products of reactions of amines with ketones and aldehydes, alkyl halides and tosylates, acid chlorides, sulfonyl chlorides, nitrous acid, and oxidizing agents. Propose mechanisms where appropriate. 

Dipotassium Iron tetracartxsnyl in the synthesis of aldehydes and ketones from alkyl halides. 

The deprotonation of an jp -hydrogen a to nitrogen has been developed into a highly useful synthetic tool in recent years. - Although some authors have suggested that this type of reactivity is a reversal of the normal reactivity adjacent to nitrogen, we submit that this notion is inappropriate and should be discontinued. The a-deprotonation of dimethyldodecylamine and triethylamine was reported over 20 years ago. In 1984, Ahlbrecht reported that j-butylpotassium readily deprotonates N-methylpiperidine, N-methylpyrrolidine and triethylamine, and that the derived organometallics add readily to aldehydes, ketones and alkyl halides. An example is shown in Scheme 1. 

BUjSnH. The reagent can be used to reduce aldehydes, ketones, and alkyl halides. 

The fact that Si—O bonds are strong is used in stabilizing enol forms of various carbonyl compounds. Generally, a base such as i-Pr2NLi (LDA) is used to deprotonate the carbonyl compound, and Me3SiCl then gives the silyl enol ether, which can react with a wide variety of carbon electrophiles, such as aldehydes, ketones, 3° alkyl halides, and a,3-unsaturated ketones, for example ... 

Katritzky and his co-workers have extended their investigations of the use of heterocycles in organic synthesis to give a synthesis of aldehydes and ketones from alkyl halides (Scheme 4). The same reagents can be used to effect the oxidation of primary amines to aldehydes, again in high yield (Scheme 5). ... 

Corey-Fuchs reaction is a two step reaction converting an aldehyde to an alkyne by one-carbon homologation of the aldehyde. The Wittig-like reaction of aldehyde 1 and dibromocarbene forms dibromoalkene 2. The treatment of dibromoalkene 2 with two equivalent of -BuLi form a lithium alkynylide, quenched by eletrophiles, such as proton, CO2, aldehydes, ketones, and alkyl halides to form alkyne 3. 

Hashemi et al. (2004) synthesized aromatic aldehydes and ketones from alkyl halides without solvent using wet montmorillonite KIO supported iodic acid as oxidant. 

These compounds are sources of the nucleophilic anion RC=C and their reaction with primary alkyl halides provides an effective synthesis of alkynes (Section 9 6) The nucleophilicity of acetylide anions is also evident m their reactions with aldehydes and ketones which are entirely analogous to those of Grignard and organolithium reagents... 

Organozmc reagents are not nearly as reactive toward aldehydes and ketones as Grig nard reagents and organolithium compounds but are intermediates m certain reactions of alkyl halides... 

Because etiolate anions are sources of nucleophilic carbon one potential use m organic syn thesis IS their reaction with alkyl halides to give a alkyl denvahves of aldehydes and ketones... 

In practice this reaction is difficult to carry out with simple aldehydes and ketones because aldol condensation competes with alkylation Furthermore it is not always possi ble to limit the reaction to the introduction of a single alkyl group The most successful alkylation procedures use p diketones as starting materials Because they are relatively acidic p diketones can be converted quantitatively to their enolate ions by weak bases and do not self condense Ideally the alkyl halide should be a methyl or primary alkyl halide... 

Nitriles contain the —C=N functional group We have already discussed the two mam procedures by which they are prepared namely the nucleophilic substitution of alkyl halides by cyanide and the conversion of aldehydes and ketones to cyanohydrins Table 20 6 reviews aspects of these reactions Neither of the reactions m Table 20 6 is suitable for aryl nitriles (ArC=N) these compounds are readily prepared by a reaction to be dis cussed m Chapter 22... 

Section 20 18 Nitnles are prepared by nucleophilic substitution (8 2) of alkyl halides with cyanide ion by converting aldehydes or ketones to cyanohydrins (Table 20 6) or by dehydration of amides... 

Lithium dialkylamides are excellent bases for making ketone enolates as well Ketone enolates generated m this way can be alkylated with alkyl halides or as illus trated m the following equation treated with an aldehyde or a ketone... 

The dianions derived from furan- and thiophene-carboxylic acids by deprotonation with LDA have been reacted with various electrophiles (Scheme 64). The oxygen dianions reacted efficiently with aldehydes and ketones but not so efficiently with alkyl halides or epoxides. The sulfur dianions reacted with allyl bromide, a reaction which failed in the case of the dianions derived from furancarboxylic acids, and are therefore judged to be the softer nucleophiles (81JCS(Pl)1125,80TL505l). 

Aldehyde or ketone synthesis by reaction ol an alkyl halide with the so< un salt of 2-mtroalkanes. 

Sodium (metal). Used as a fine wire or as chips, for more completely drying ethers, saturated hydrocarbons and aromatic hydrocarbons which have been partially dried (for example with calcium chloride or magnesium sulfate). Unsuitable for acids, alcohols, alkyl halides, aldehydes, ketones, amines and esters. Reacts violently if water is present and can cause a fire with highly flammable liquids. 

Lithium aluminum hydride (LiAlH4) is the most powerful of the hydride reagents. It reduces acid chlorides, esters, lactones, acids, anhydrides, aldehydes, ketones and epoxides to alcohols amides, nitriles, imines and oximes to amines primary and secondary alkyl halides and toluenesulfonates to... 

OL Alkylation of aldehydes and ketones (Section 18.15) Alkylation of simple aldehydes and ketones via their enolates is difficult. p-Diketones can be converted quantitatively to their enolate anions, which react efficiently with primary alkyl halides. 

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