A Convenient Palladium‐Catalyzed Carbonylative Synthesis of (E)‐3‐Benzylidenechroman‐4‐ones

A convenient palladium‐catalyzed carbonylation reaction for the efficient synthesis of (E)‐3‐benzylidenechroman‐4‐ones has been developed. Using TFBen as a solid CO source, a range of substituted (E)‐3‐benzylidenechroman‐4‐ones were prepared in moderate to good yields with 2‐iodophenols and allyl chlorides as the substrates. Additionally, substituted quinolin‐4(1H)‐ones can also be obtained with 2‐iodoaniline as the starting material. Cascade reactions: A palladium‐catalyzed carbonylation reaction for the synthesis of benzylidenechromanone has been developed. Using 2‐iodophenols and allyl chlorides as the substrates, a range of substituted benzylidenechromanones were prepared in moderate to good yields. Additionally, substituted quinolin‐4(1H)‐one derivatives could also be obtained when 2‐iodoanilines were used (see scheme).