Organometallic compounds with acyl halides

First, coordinatively unsaturated active palladium catalyst, PdL2, is produced via dissociation of the ligands, which then reacts with acyl halide to give the acylpalladium intermediate. Since deinsertion of CO of the acylpalladium derivatives may occur simul-taneously, the next step, transmetallation (so-called metathesis), is the most crucial for the efficiency of the overall reaction. A variety of organometallic compounds, such as boron, aluminum, copper, zinc, mercury, silicon, tin, lead, zirconium, and bismuth, are used as the partner in this coupling reaction without loss of CO. In this section, the important features of the cross-coupling reactions of a variety of organometallic compounds with acyl halides and related electrophiles are discussed. 

Many other types of organometallics which are not acylated directly acid chlorides and which do not undergo addition to ketones may still transmetallate into the acylpalladiumfll) complex. Simple alkyl organomercurials have been acylated in this fashion to give moderate to good yields of ketones. " Larock has studied the palladium-catalyzed acylation of vinylmercury(II) compounds with acyl halides (equation 104). The reaction was only modestly productive and could not compare to the yield provided by aluminum chloride catalysis. 

Palladium-catalyzed coupling reactions of organozinc compounds with acyl halides are the fastest and mildest among the known methods using a variety of organometallic compounds. 

Other organometallic compounds have also been utilized for the coupling reaction with acyl halides. 

The Conversion of Acyl Halides to Ketones With Organometallic Compounds ... 

Organopalladium intermediates are also involved in the synthesis of ketones and other carbonyl compounds. These reactions involve acylpalladium intermediates, which can be made from acyl halides or by reaction of an organopalladium species with carbon monoxide. A second organic group, usually arising from any organometallic reagent, can then form a ketone. Alternatively, the acylpalladium intermediate may react with nucleophilic solvents such as alcohols to form esters. 

II c., Cl 0 M L- X c Reaction of acyl halides or other acid derivatives with organometallic compounds... 

Acylation is one of the most fundamental and useful reactions in organic synthesis and is normally achieved by the reaction either with carboxylic acid derivatives and organometallic compounds or with masked acyl anions and aUcyl halides. 

Reaction of halo ketones or diazo ketones with boranes 0-102 Carbonylation of alkyl halides 0-104 Reaction between acyl halides and organometallic compounds 0-105 Reaction between other acid derivatives and organometallic compounds... 

Organonitrogen-lithium compounds, and particularly lithium amides (R2NLi), are widely used both in organic and in organometallic syntheses. For the former, these strong bases are employed as proton abstractors (5-8), to generate new organolithiums. These can then be derivatized with so-called electrophiles, e.g., alkyl and acyl halides (E+ = R+ and R—C+=0) and trimethylsilylchloride (E+ = MeaSi+) [Eq. (1)]. 

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