An organocatalytic domino Michael-alkylation reaction: highly enantioselective construction of spiro-cyclopentanoneoxindoles and tetronic acid scaffolds.
نویسندگان
چکیده
A new organocatalytic asymmetric domino Michael-alkylation reaction of methyleneindolinones and γ-halogenated-β-ketoesters is described. A variety of spiro-cyclopentanoneoxindoles were obtained in high yields (up to 96%), good diastereoselectivities (up to 12 : 1 dr) and excellent enantioselectivities (up to >99% ee) via α-alkylation. Interestingly, O-alkylated products with tetronic acid motifs could be obtained by tuning the N-protecting groups on methyleneindolinones with excellent enantioselectivities (up to >99% ee).
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ورودعنوان ژورنال:
- Chemical communications
دوره 50 93 شماره
صفحات -
تاریخ انتشار 2014