This communication describes the discovery of air-stable and highly versatile B-protected haloalkenylboronic acid building blocks for iterative cross-coupling. These reagents enable the total synthesis of polyene natural products with extraordinary levels of simplicity, efficiency, and modularity. Specifically, all-trans-retinal, β-parinaric acid, and one-half of the amphotericin B macrolide skeleton were prepared using only the Suzuki-Miyaura reaction ...