Recent trends in research have gained an orientation toward developing efficient strategies using innocuous reagents. The earlier reported transition-metal-catalyzed carbonylations involved either toxic carbon monoxide (CO) gas as carbonylating agent or functional-group-assisted ortho sp(2) C-H activation (i.e., ortho acylation) or carbonylation by activation of the carbonyl group (i.e., via the formation of enamines). Contradicting these methods, here we describe an environmentally benign process, [Pd]-catalyzed direct carbonylation starting from simple and commercially available iodo arenes and aldehydes, for the synthesis of a wide variety of ketones. Moreover, this method comprises direct coupling of iodoarenes with aldehydes without activation of the carbonyl and also without directing group assistance. Significantly, the strategy was successfully applied to the synthesis n-butylphthalide and pitofenone.
The presence of nitrogen atom in a wide variety of organic compounds called for the use of powerful CÀ H activation strategy in the CÀ N bond formation. Pentamethylcyclopentadienyl (Cp*) based, high-valent, group 9 transition-metal complexes have shown a great potential as catalysts in the CÀ H activation/functionalization over the years. This minireview summarizes recent progress made in the context of CÀ N bond formation via catalytic (sp 2)CÀ H activation with Cp*M(III) (M = Co, Rh and Ir) catalysts. A general plausible mechanism is briefly discussed at the beginning, and then results are arranged according to metal cobalt, rhodium and iridium, respectively.
An efficient, one-pot synthesis of substituted indenones was accomplished starting from simple o-iodoketones and aldehydes. [Pd]-catalyzed direct acylation of o-iodoketones with aldehydes was employed as the key step. Subsequent intramolecular aldol condensation afforded the indenones. Notably, a variety of indenones were achieved. Significantly, the natural product neolignan was accomplished in one pot.
Transition‐metal‐ as well as ligand‐free base‐mediated domino isomerization and alkylation of allylic alcohols is presented. This protocol features the conversion of simple allylic alcohols into the corresponding ketones through isomerization in the presence of a simple base. Significantly, these in situ generated ketones subsequently undergo alkylation with styrenes as electrophiles, in a domino one‐pot fashion, as an atom‐ and step‐economical chemical process.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.