Alkynes acylation

Addition of carboxylic acids to alkynes Acylation of aldehydes or ketones Bisdecarboxylation of malonic acids Oxidation of arylmethanes with CrOs and AC2O... 

Reduction of Co2(CO)g with sodium-amalgam in THF solution gives Na[Co(CO)4]. Na[Co(CO)4] has high nucleophilicity, and the reaction with alkyl halides gives alkyl-cobalt complexes. It is generally difficult to isolate the alkylcobalt complexes, but in the presence of alkenes and alkynes, acylated compounds are obtained in good yields (eq (10)) [13]. 

From these two reviews [16, 18], this section shows aUcenylations (reactions with alkenes), alkynylations (reactions with alkynes), acylations, carbonylations, isocya-nations, and halogenations as applications for organometallic intramolecular-coordination five-membered products, as seen in Eqs. (7.14)-(7.44) and Schemes 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 7.10, 7.11, and 7.12. 

Santelli has demonstrated that aUenylsUanes without a C-1 substituent undergo conjugate addition to Q , -unsaturated acyl cyanides to give 5,e-alkynic acyl cyanides. ... 

Formation of C-N bond has raised of interest in the scientific community in the last 10 years. In this context, the formation of enamides is a valuable protocol. In addition to conventional approaches that include condensation of amides and aldehydes, addition of amides to alkynes, acylation of imines, Curtius rearrangement of a,jS-unsaturated acyl azides, amide Peterson olefination, and Wittig and Horner-Wadsworth-Emmons reactions, several transition metal-catalyzed methods have been developed that allow the synthesis of enamides.Inspired by the analogous arylation of amines catalyzed by palladium or copper complexes (Buchwald-Hartwig reaction), a new approach for the synthesis of enamides has been published recently, which allows to prepare enamides from readily available starting materials (amides and vinyl halides) proceeding under very mild conditions. Thus, we decided to test the Porco-Buchwald amidation of vinyl halides in our synthesis [144-146]. 

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