Enantioselective Synthesis of Spirobarbiturate-Cyclohexenes through Phosphine-Catalyzed Asymmetric [4+ 2] Annulation of Barbiturate-Derived Alkenes with …

~87%

~88%

~84%

~91%

~92%

~92%

~86%

~81%

~92%

~87%

~82%

~78%

~87%

~86%