Efficient one-pot quinoline derivative synthesis from acetophenone and allyl alcohols

Quinoline derivatives are widely found in pharmaceuticals, agrochemicals, and functional materials, and the development of efficient synthetic methods for these compounds has attracted considerable attention. In this study, we reported a strategy employing <i>O</i>-sulfonylhydroxylamine (HOSA) as a novel transient directing group (TDG) to achieve site-selective <i>ortho</i> C-H functionalization/cyclization of acetophenones with allyl alcohols. This reaction system operated under mild and readily tunable conditions, enabling efficient construction of the quinoline scaffold <i>via</i> a one-pot process. Our investigations revealed that the structure of the transient directing group, solvent, and reaction temperature collectively govern the reaction pathway, allowing precise control over product selectivity. This approach exhibited broad substrate scope and excellent functional group tolerance. This work not only represented the first application of HOSA as an efficient and versatile catalytic transient directing group in C-H cyclization reactions, but also provided a practical and valuable route for the synthesis of quinoline derivatives.