Stille coupling is a palladium-catalyzed cross-coupling between an organostannane and an organic electrophile, usually an aryl, vinyl, allyl, or acyl halide or pseudohalide, that forms a new carbon–carbon bond. The catalytic cycle comprises oxidative addition of the electrophile to Pd(0), transmetalation that transfers the organic group from tin to palladium, and reductive elimination of the coupled product while regenerating Pd(0) ^[1]. The carbon group bound to tin is transferred with retention of its basic carbon skeleton, whereas the other substituents on tin generally remain in an organotin byproduct. Ligands, additives, electrophile identity, and the relative transfer aptitude of groups on tin control rate and chemoselectivity. The defining organometallic partner is an organotin reagent; organosilicon compounds instead participate in Hiyama coupling, and organoboron compounds in Suzuki–Miyaura coupling. Stille's account of palladium-catalyzed coupling of organotin reagents with organic electrophiles establishes this specific reaction boundary ^[2].