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A metal-catalyst-free intramolecular Heck carbonylation reaction of benzyl alcohols and benzyl amines with carbon monoxide under heating at 250 °C affords the corresponding benzolactones and benzolactams in good to excellent yields. A hybrid radical/ionic chain mechanism, involving electron transfer from radical anions generated by nucleophilic attack of alcohols or amines on intermediate acyl radicals, is proposed. [ABSTRACT FROM AUTHOR]

The bromine-radical-mediated allylation reaction of aldehydes was studied. In the presence of V-65 as radical initiator, the reaction of aldehydes with allyl bromides gave β,γ-unsaturated ketones in good yields (13 examples, 45-84%). The reaction is triggered by hydrogen abstraction from the aldehyde by bromine radical to form an acyl radical, which undergoes an SH2′-type addition-elimination reaction with allyl bromides to give coupling products with liberation of bromine radical. Three-component coupling reactions comprising aldehydes, electron-deficient alkenes, and methallyl bromide also proceeded to give δ,ε-unsaturated ketones. [ABSTRACT FROM AUTHOR]

Ruthenium complex [RuCl2(CO)3]2 catalyzes the addition of 1,3-diketones to terminal alkynes. We observed C-addition with acyclic 1,3-diketones, whereas the use of cyclic 1,3-diketones systematically led to O-addition reactions. [ABSTRACT FROM AUTHOR]