Vinylidene compounds are a class of organic molecules characterized by the presence of a vinylidene group, which has the structure R2C=C. These compounds typically feature a double bond between two carbon atoms, with one of the carbons bonded to two other groups. Vinylidene compounds are important in various chemical reactions and can serve as intermediates in the synthesis of more complex molecules. These compounds are often used in the production of polymers and plastics, such as polyvinylidene fluoride (PVDF), which is known for its chemical resistance and durability. Vinylidene compounds can also be found in some natural products and are studied for their potential applications in materials science and organic synthesis.