Highly efficient asymmetric vinylogous Mannich reaction induced by O-pivaloylated D-galactosylamine as the chiral auxiliary.
نویسندگان
چکیده
The diastereospecific formation of β-N-glycoside-linked α-amino-2(5H)-furanone has been achieved with high yield via a vinylogous Mannich reaction. The reaction was performed by using O-pivaloylated galactosylamine 1 as a chiral template and ZnCl(2)·Et(2)O as a promoter in Et(2)O. Imines 3 of aromatic compounds and trimethylsiloxyfuran 4 were converted to N-galactosyl α-amino-2(5H)-furanone 5, giving ratios of diastereomers higher than 20:1. This procedure provides rapid access to biologically important γ-butenolide derivatives.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 9 6 شماره
صفحات -
تاریخ انتشار 2011