title: Amino acid derived phosphine-catalyzed enantioselective 1,4-dipolar spiroannulation of cyclobutenones and isatylidenemalononitrile.
abstract: Cyclobutenones have been explored as a new type of chiral 1,4-dipole four-carbon synthon, which readily undergoes organophosphine-mediated C-C bond cleavage and asymmetric intermolecular 1,4-dipolar spiroannulation with isatylidenemalononitrile in the presence of amino acid-derived chiral phosphine catalyst to furnish enantioenriched 3-spirocyclohexenone 2-oxindoles in good yield with up to 87% ee. To our knowledge, this is the first example of asymmetric transformation of cyclobutenones and the phosphine-catalyzed asymmetric 1,4-dipolar cycloaddition consisting of C-C bond activation is unprecedented.
authors: Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, East China Normal University, 3663, N. Zhongshan Road, Shanghai, 200062 (P.R. China) http://faculty.ecnu.edu.cn/s/1811/main.jspy.
authors: Yangyan
authors: Y
authors: Li
authors: Xiao
authors: X
authors: Su
authors: Wei
authors: W
authors: Zhou
authors: Wenbo
authors: W
authors: Li
authors: Junliang
authors: J
authors: Zhang
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D002384:Catalysis; D003503:Cyclobutanes / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D010720:Phosphines / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D003503:Cyclobutanes; D010720:Phosphines; C553737:cyclobutenone; C044646:phosphine
keywords: CC bond activation; organocatalysis; oxindoles; phosphanes; spiroannulation