One-pot synthesis of 2-hydroxymethylindoles via photoredox-catalyzed ketyl-ynamide coupling/1,3-allylic alcohol transposition

An efficient visible-light-mediated ketyl-ynamide coupling by employing ynamides bearing alkyl sulfonyl substituents to deliver eneindolin-3-ols has been developed. Subsequent 1,3-transposition of allylic alcohols in one pot is capable of synthesizing 2-hydroxymethylindoles in generally moderate to good yields. The synthetic utility of this protocol has also been demonstrated by the facile and practical synthesis of two bioactive molecules. The use of readily available substrates, a simple procedure and benign reaction conditions render this method a viable alternative for the synthesis of 2-hydroxymethylindoles.