Highly diastereo- and enantioselective NHC-catalyzed [3+2] annulation of enals and isatins.
نویسندگان
چکیده
The chiral N-heterocyclic carbene bearing a proximal hydroxy group derived from L-pyroglutamic acid was found to be an efficient catalyst for the [3+2] annulation of enals and isatins to give the corresponding spirocyclic oxindolo-γ-butyrolactones in good yield with good diastereo- and enantioselectivities.
منابع مشابه
Enantioselective Assembly of Spirolactones through NHC-Catalyzed Remote γ-Carbon Addition of Enals with Isatins.
A chiral N-heterocyclic carbene (NHC)-catalyzed formal [4 + 2] annulation of β-methyl substituted enals with isatins was developed to construct six-membered spirolactones bearing highly congested quaternary carbon stereocentersin good yields and high enantioselectivities. The strategy realized a challenging remote γ-carbon addition of enals and chiral control of β-methyl substituted enals in th...
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عنوان ژورنال:
- Chemical communications
دوره 47 36 شماره
صفحات -
تاریخ انتشار 2011