title: Organocatalytic enantioselective 1,3-dipolar cycloadditions between Seyferth-Gilbert reagent and isatylidene malononitriles: synthesis of chiral spiro-phosphonylpyrazoline-oxindoles.
abstract: A new method has been developed for the catalytic enantioselective 1,3-dipolar cycloaddition of the Seyferth-Gilbert reagent (SGR) to isatylidene malononitriles using a cinchona alkaloid derivative as a catalyst. This method allowed for the synthesis of a series of chiral spiro-phosphonylpyrazoline-oxindoles in good yields with excellent enantioselectivities. The synthetic utility of this method was further demonstrated by its use in a three-component domino reaction involving isatin, malononitrile, and SGR based on sequential Knoevenagel condensation and 1,3-dipolar cycloaddition reactions.
authors.affiliation: Key Laboratory of Applied Chemistry of Chongqing Municipality, School of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, China.
authors.forename: Taiping
authors.initials: T
authors.lastname: Du
authors.forename: Fei
authors.initials: F
authors.lastname: Du
authors.forename: Yanqiang
authors.initials: Y
authors.lastname: Ning
authors.forename: Yungui
authors.initials: Y
authors.lastname: Peng
mesh_terms: D002930:Cinchona Alkaloids / Q000737:chemistry*; D061565:Cycloaddition Reaction; D007202:Indicators and Reagents / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D007510:Isatin / Q000737:chemistry*; D015394:Molecular Structure; D009570:Nitriles / Q000737:chemistry*; D000078183:Oxindoles; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D002930:Cinchona Alkaloids; D007202:Indicators and Reagents; D007211:Indoles; D009570:Nitriles; D000078183:Oxindoles; D013141:Spiro Compounds; C022960:2-oxindole; D007510:Isatin; C000945:dicyanmethane