4-Aryl- and 4-Vinyl-2,2-Dialkyl-3-chromenes from Tertiary 3-(o-Bromophenyl)propynols via a Palladium-Catalyzed Hydroarylation/Hydrovinylation-Cyclization Sequence
4-Aryl- and 4-Vinyl-2,2-Dialkyl-3-chromenes from Tertiary 3-(o-Bromophenyl)propynols via a Palladium-Catalyzed Hydroarylation/Hydrovinylation-Cyclization Sequence