Visible‐Light‐Driven Remote C(sp ² )—H Silylation/Cyclization of <i>N</i> ‐Cyanamide Alkenes: A General and Efficient Access to Silylated Pyrrolo[2,1‐b]quinazolinones

A visible‐light‐driven domino silylation/cyclization of N ‐cyanamide alkenes has been developed, enabling remote C( sp 2 )—H functionalization under mild and green conditions. This protocol provides an efficient and sustainable route to synthetically valuable silylated pyrrolo[2,1‐ b ]quinazolinones through the simultaneous formation of three bonds and two rings in a single operation. The reaction proceeds without external oxidants, employing an earth‐abundant nickel catalyst, exhibits high atom economy, and releases only H 2 as the byproduct, aligning with the principles of green chemistry. Mechanistic investigations support a radical pathway involving silyl radical addition and intramolecular cyano cyclization. Several of the synthesized compounds demonstrate promising antitumor activities, highlighting the potential of this method in medicinal chemistry and sustainable synthesis.