No abstract

We describe transfer carbonylation reactions of 2‐bromoarenes that contain a carbon‐nucleophile using aldehydes as a substitute for CO, leading to the formation of indanone derivatives. The transformation proceeds efficiently under RhI/Pd0‐hybrid catalytic conditions consisting of two discrete transition metals, rhodium and palladium, which catalyze the decarbonylation of aldehydes and the subsequent carbonylation of bromoarenes using the resulting carbonyl moiety, respectively. The majority of the abstracted CO is transferred directly to the product via a CO‐relay process from rhodium to palladium.

15 years have gone by since the first report on transfer carbonylation, which avoids the direct use of carbon monoxide. Subsequently, this field has attracted considerable attention, especially over the past five years carbon monoxide substitutes, such as aldehydes and formates, have been widely used for in situ and ex situ generation of CO. This paper describes the verification of a new strategy involving two discrete transition metals, rhodium and palladium, which catalyze the decarbonylation of aldehyde and the subsequent carbonylation of bromoarenes, respectively. The dual catalysis involves the CO‐relay between the first runner (Rh) and the second runner (Pd) as if a baton. More information can be found in the Communication by Tsumoru Morimoto et al. on page 473 in Issue 4, 2020 (DOI: 10.1002/asia.201901595).