Carbonylation and Reactions of Acyl Chlorides

Cavicchioli, D. Bouyssi,). Gore, andG. Bahne, Tetrahedron Lett., 37,1429(1996). 

Sridharan, V. Tambyrajah, and M. Thomton-Pett, Tetrahedron, 54, 2595 (1998). 

Aryl and alkenyl halides and triflates undergo Pd-catalyzed carbonylation, offering useful synthetic methods for carboxylic acids, esters, amides, aldehydes and ketones. Facile CO insertion into aryl- or alkenylpalladium complexes generates acylpalladium intermediates 1. The intermediates are attacked by several 

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The characteristic reaction of acyl chlorides acid anhydrides esters and amides is nucleophilic acyl substitution Addition of a nucleophilic reagent Nu—H to the carbonyl group leads to a tetrahedral mtermedi ate that dissociates to give the product of substitution... 

Oxoindolizines are obtained by reaction of ethyl pyrrolidinylideneacetate with several acyclic unsaturated carbonyl compounds by cyclization of the formed Michael adducts104 (equation 73). When this reaction was modified by changing the ring size of the enaminoester, the substitution pattern of the enone structure and by varying the conditions, different products were isolated105. N-acylation could be accomplished by reaction of acyl chlorides in the presence of pyridine. Bicyclic lactams are yielded by Michael addition of acrylic esters and NaH (equation 74). 

In the same way, the coupling reaction of acyl chlorides and organotins is particularly efficient and general . This represents an alternative to the carbonylative three-component coupling reaction, and gives access to various aldehydes, ketones and a, fi-unsaturated ketones. A similar reaction is feasible with chloroformates, carbamoyl chlorides and snlphonyl chlorides, giving respectively a, -unsaturated esters, amides and sulphones . ... 

Whilst reaction of acyl chloride 303 with Na[Co(CO)3(PEt3)] affords the oxocyclobut-enyl complex 306" by ring expansion and CO loss, analogous treatment with NaRe(CO)5 delivers the non-fluxional // -cyclopropenylrhenium compound 305" . In the latter case, compound 304 loses carbon monoxide with concomitant migration of the cyclopropenyl moiety from carbonyl to rhenium as an allylic rearrangement rather than a 1,2-shift. 

The acylpalladium is formed by CO insertion as the intermediate of the carbonylation. They can be prepared directly by the oxidative addition of acyl chlorides to Pd(0). Thus ketones can be prepared by the reaction of acyl halides with organozinc reagents and organostannanes. Benzoacetate (490) is obtained by the reaction of benzoyl chloride with the Reformatsky reagent 489 [243], The macrocyclic keto lactone 492 is obtained by intramolecular reaction of the alkenylstannane with acyl chloride in 491 [244]. 

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